0001438133-25-000036 | 10-K | XBRL Viewer

Print Document

Stockholders' Equity - Summary of Stock Option Activities for 2006 Plan and 2013 Plan (Detail) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward]
Options, Outstanding at beginning of period (in shares)	3,896,004	4,442,313	4,814,846
Options, Granted (in shares)	0	0	83,008
Options, Exercised (in shares)	(112,171)	(72,536)	(280,275)
Options, Canceled/forfeited (in shares)	(257,277)	(473,773)	(175,266)
Options, Outstanding at end of period (in shares)	3,526,556	3,896,004	4,442,313	4,814,846
Options, Vested and expected to vest at December 31, 2024 (in shares)	3,525,815
Options, Exercisable at December 31, 2024 (in shares)	3,496,909
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price [Abstract]
Weighted-Average Exercise Price Per Share, Outstanding at beginning of period (in dollars per share)	$ 54.79	$ 57.95	$ 57.08
Weighted-Average Exercise Price Per Share, Granted (in dollars per share)	0	0	65.28
Weighted-Average Exercise Price Per Share, Exercised (in dollars per share)	19.90	17.86	32.58
Weighted-Average Exercise Price Per Share, Canceled/forfeited (in dollars per share)	85.51	90.14	77.93
Weighted-Average Exercise Price Per Share, Outstanding at end of period (in dollars per share)	53.65	$ 54.79	$ 57.95	$ 57.08
Weighted-Average Exercise Price Per Share, Vested and expected to vest at December 31, 2024 (in dollars per share)	53.65
Weighted-Average Exercise Price Per Share, Exercisable at December 31, 2024 (in dollars per share)	$ 53.44
Weighted- Average Remaining Contractual Life (in years)	4 years 3 months 25 days	5 years 3 months 18 days	6 years 1 month 13 days	7 years 25 days
Weighted-Average Remaining Contractual Life, Vested and expected to vest	4 years 3 months 25 days
Weighted-Average Remaining Contractual Life, Exercisable	4 years 3 months 18 days
Aggregate intrinsic value outstanding balance	$ 16,147	$ 11,703	$ 30,236	$ 452,081
Aggregate Intrinsic Value, Exercised	2,483	1,400	13,473
Aggregate Intrinsic Value, Canceled/forfeited/expired	0	$ 95	$ 2,143
Aggregate Intrinsic Value, Vested and expected to vest	16,147
Aggregate Intrinsic Value, Exercisable	$ 16,147

Composition of Certain Financial Statement Items - Accounts Receivable (Details) - USD ($) $ in Thousands	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Accounts receivable	$ 121,836	$ 110,453
Less: allowance for credit losses	(7,251)	(4,898)	$ (4,327)	$ (4,249)
Accounts receivable, net	$ 114,585	$ 105,555

Short-Term Investments - Contractual Maturities of Available - For- Sale Debt Securities (Details) $ in Thousands	Dec. 31, 2024 USD ($)
Cash Cash Equivalents And Short Term Investments [Line Items]
Within One Year	$ 213,895
One to Two Years	101,822
Two to Three Years	53,378
Estimated Fair Value	369,095
United States Government-sponsored enterprises
Cash Cash Equivalents And Short Term Investments [Line Items]
Within One Year	44,717
One to Two Years	39,193
Two to Three Years	49,370
Estimated Fair Value	133,280
United States Treasury securities
Cash Cash Equivalents And Short Term Investments [Line Items]
Within One Year	85,400
One to Two Years	17,307
Two to Three Years	995
Estimated Fair Value	103,702
Commercial paper
Cash Cash Equivalents And Short Term Investments [Line Items]
Within One Year	23,264
One to Two Years	0
Two to Three Years	0
Estimated Fair Value	23,264
Corporate debt securities
Cash Cash Equivalents And Short Term Investments [Line Items]
Within One Year	60,514
One to Two Years	45,322
Two to Three Years	0
Estimated Fair Value	105,836
Foreign government bonds
Cash Cash Equivalents And Short Term Investments [Line Items]
Within One Year	0
One to Two Years	0
Two to Three Years	3,013
Estimated Fair Value	$ 3,013

Composition of Certain Financial Statement Items

12 Months Ended

Dec. 31, 2024

Organization, Consolidation and Presentation of Financial Statements [Abstract]

Composition of Certain Financial Statement Items

Accounts Receivable

Accounts receivable, net consisted of the following at December 31, 2024 and December 31, 2023 (in thousands):


	December 31,		December 31,
	2024		2023

Accounts receivable	$	121,836	$	110,453
Less: allowance for credit losses	(7,251)		(4,898)
Accounts receivable, net	$	114,585	$	105,555

Allowance for Credit Losses

The following table provides a reconciliation of the changes in the allowance for estimated accounts receivable credit losses for the years ended December 31, 2024 and 2023 (in thousands):


	Year Ended December 31,
		2024		2023		2022
Balance at beginning of the period		$	4,898	$	4,327	$	4,249
Provision for expected credit losses		9,979		5,540		4,782
Write-offs and adjustments, net of recoveries		(7,626)		(4,969)		(4,704)
Balance at end of the period		$	7,251	$	4,898	$	4,327

Inventories

Inventories consisted of the following at December 31, 2024 and December 31, 2023 (in thousands):


	December 31,		December 31,
	2024		2023

Raw materials	$	32,602	$	42,783
Work-in-process	33,517		44,026
Finished goods	83,493		71,128
Total inventories	$	149,612	$	157,937

Property and Equipment

Property and equipment, net consisted of the following at December 31, 2024 and 2023 (in thousands):


	December 31,
	2024		2023
Leasehold improvements	$	37,106	$	37,565
Office furniture and equipment	11,813		11,842
Computer equipment and software	9,811		10,340
Manufacturing and scientific equipment	82,248		69,589
Total cost	140,978		129,336
Less: accumulated depreciation and amortization	(62,828)		(52,794)
Total property and equipment, net	$	78,150	$	76,542

Depreciation and amortization expense related to property and equipment was $14.7 million, $13.8 million, and $12.3 million for the years ended December 31, 2024, 2023 and 2022, respectively.

Intangible Assets Subject to Amortization

Intangible assets subject to amortization consist of technology-based intangibles related to the Company’s acquisition of Sugarmate, as well as patents purchased or licensed that are related to the Company’s commercialized products. Intangible assets at December 31, 2024 and 2023, which were included in other long-term assets on the consolidated balance sheets, were as follows (in thousands):


	December 31,
	2024		2023
Intangible assets, gross amount	$	12,502	$	12,502
Accumulated amortization	(11,577)		(9,726)
Intangible assets, net	$	925	$	2,776
Weighted average remaining amortization period (in months)	6		18

Amortization expense related to intangible assets subject to amortization amounted to $1.9 million, $1.9 million and $2.0 million for the years ended December 31, 2024, 2023 and 2022, respectively. The amortization expense is recorded in selling, general and administrative expense in the consolidated statement of operations. The estimated aggregate future amortization expense is $0.9 million in 2025, all of which will be recorded in selling, general and administrative expense in the consolidated statement of operations.

CONSOLIDATED BALANCE SHEETS - USD ($) $ in Thousands	Dec. 31, 2024	Dec. 31, 2023
Current assets:
Cash and cash equivalents	$ 69,234	$ 58,868
Short-term investments	369,095	409,044
Accounts receivable, net	114,585	105,555
Inventories	149,612	157,937
Prepaid and other current assets	21,965	16,585
Total current assets	724,491	747,989
Property and equipment, net	78,150	76,542
Operating lease right-of-use assets	85,306	87,791
Equity method investments	74,545	0
Other long-term assets	5,166	40,336
Total assets	967,658	952,658
Current liabilities:
Accounts payable	44,730	49,586
Accrued expenses	18,170	12,726
Employee-related liabilities	64,128	43,430
Current portion of convertible senior notes, net	40,670	0
Operating lease liabilities	18,208	17,060
Deferred revenue	11,831	43,994
Other current liabilities	49,312	28,462
Total current liabilities	247,049	195,258
Convertible senior notes, net - long-term	308,266	285,035
Operating lease liabilities - long-term	106,421	113,572
Deferred revenue - long-term	10,455	13,331
Other long-term liabilities	32,369	31,830
Total liabilities	704,560	639,026
Commitments and contingencies (Note 13)	0	0
Stockholders’ equity:
Common stock, $0.001 par value; 200,000 shares authorized, 66,264 and 65,552 shares issued and outstanding at December 31, 2024 and December 31, 2023, respectively.	66	66
Additional paid-in capital	1,312,804	1,263,997
Accumulated other comprehensive income (loss)	(1,947)	1,369
Accumulated deficit	(1,047,825)	(951,800)
Total stockholders’ equity	263,098	313,632
Total liabilities and stockholders’ equity	$ 967,658	$ 952,658

CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Operating Activities
Net loss	$ (96,025)	$ (222,611)	$ (94,594)
Adjustments to reconcile net loss to net cash provided by (used in) operating activities:
Depreciation and amortization expense	16,607	15,715	14,330
Amortization of debt issuance costs	2,089	2,204	1,896
Provision for expected credit losses	9,979	5,540	4,782
Operating lease termination and other impairment charges	2,000	14,099	7,567
Accretion (amortization) of discount or premium on short-term investments	(2,321)	3,587	4,187
Losses from equity method investee	2,053	0	0
Stock-based compensation expense	101,383	88,076	84,918
Loss on extinguishment of debt	1,268	0	0
Acquired in-process research and development expenses	0	78,750	31,039
Other	(1,027)	515	988
Changes in operating assets and liabilities:
Accounts receivable, net	(20,795)	4,277	(7,830)
Inventories	5,810	(46,053)	(42,452)
Prepaid and other current assets	(5,565)	(9,139)	(58)
Other long-term assets	893	(3,187)	(1,207)
Accounts payable and accrued expenses	(2,392)	(4,864)	24,493
Accrued expenses	5,550	2,537	(461)
Employee-related liabilities	20,859	5,167	(12,869)
Deferred revenue	(34,736)	21,525	8,358
Operating leases and other current liabilities	17,597	4,302	25,445
Other long-term liabilities	998	7,750	1,932
Net cash provided by (used in) operating activities	24,225	(31,810)	50,464
Investing Activities
Purchases of short-term investments	(264,311)	(510,859)	(467,652)
Proceeds from maturities and redemptions of short-term investments	306,464	546,218	569,492
Purchases of property and equipment	(19,231)	(26,804)	(34,097)
Acquisitions, including in-process research and development, net of cash acquired	0	(69,496)	(25,720)
Purchases of equity investments, strategic investments, and intangible assets	(46,404)	(24,799)	(8,855)
Net cash provided by (used in) investing activities	(23,482)	(85,740)	33,168
Financing Activities
Proceeds from issuance of convertible senior notes due 2029, net of $9,400 debt issuance costs	306,850	0	0
Repurchase of $246,740 principal amount of convertible senior notes due 2025	(246,123)	0	0
Payment for capped call transactions related to convertible senior notes due 2029	(15,813)	0	0
Repurchase and retirement of common stock	(30,000)	0	0
Proceeds from issuance of common stock under Company stock plans, net of cash used to settle withholding taxes on vested restricted stock	(6,730)	4,184	17,469
Other financing activities	183	(71)	(592)
Net cash provided by financing activities	8,367	4,113	16,877
Effect of foreign exchange rate changes on cash	1,256	(212)	827
Net increase (decrease) in cash and cash equivalents	10,366	(113,649)	101,336
Cash and cash equivalents at beginning of period	58,868	172,517	71,181
Cash and cash equivalents at end of period	69,234	58,868	172,517
Supplemental disclosures of cash flow information
Interest paid	3,076	7,565	4,313
Income taxes paid	3,098	1,923	411
Supplemental schedule of non-cash investing and financing activities
Operating lease right-of-use assets obtained in exchange for operating lease obligations	4,370	0	114,003
Purchases of property and equipment included in accounts payable	$ 511	$ 2,946	$ 4,237

Fair Value Measurements (Tables)

12 Months Ended

Dec. 31, 2024

Fair Value Disclosures [Abstract]

Schedule of Financial Assets and Liabilities Measured at Fair Value on Recurring Basis

The following table presents information about the Company’s financial assets and liabilities measured at fair value on a recurring basis as of December 31, 2024 and December 31, 2023, and indicates the fair value hierarchy of the valuation techniques used by the Company to determine such fair value (in thousands):


	Fair Value Measurements at December 31, 2024
	Total		Level 1		Level 2		Level 3
Assets
Cash equivalents(1)	$	56,234	$	56,234	$	—	$	—
United States Government-sponsored enterprises	133,280		—		133,280		—
United States Treasury securities	103,702		103,702		—		—
Commercial paper	23,264		—		23,264		—
Corporate debt securities	105,836		—		105,836		—
Foreign government bonds	3,013		—		3,013		—

Total assets	$	425,329	$	159,936	$	265,393	$	—


	Fair Value Measurements at December 31, 2023
	Total		Level 1		Level 2		Level 3
Assets
Cash equivalents(1)	$	48,033	$	48,033	$	—	$	—
United States Government-sponsored enterprises	182,154		—		182,154		—
United States Treasury securities	115,004		115,004		—		—
Commercial paper	72,511		—		72,511		—
Corporate debt securities	39,375		—		39,375		—

Total assets	$	457,077	$	163,037	$	294,040	$	—

(1)Generally, cash equivalents include money market funds and investments with a maturity of three months or less from the date of purchase.

Schedule of Convertible Senior Notes

The Company estimated the fair value of its convertible senior notes based on Level 2 quoted market prices as follows (in thousands):


	Fair Value Measurements at
	December 31, 2024		December 31, 2023
Convertible Senior Notes due 2025	$	39,130	$	271,688
Convertible Senior Notes due 2029	407,752		*
Total fair value of outstanding convertible senior notes	$	446,882	$	271,688

* Not applicable as no notes were outstanding at this date.

The net carrying amount of the Company’s convertible senior notes on the consolidated balance sheets consisted of the following (in thousands):


	December 31, 2024		December 31, 2023
Principal amount:
Convertible Senior Notes Due 2025	$	40,760	$	287,500
Convertible Senior Notes Due 2029	316,250		*
Total principal amount	357,010		287,500
Unamortized debt issuance costs	(8,074)		(2,465)
Total debt, net	$	348,936	$	285,035
Less: current portion	(40,670)		—
Long-term senior convertible notes	$	308,266	$	285,035

* Not applicable as no notes were outstanding at this date.

The following table summarizes the effective interest rates for each of our convertible senior notes for the periods shown:


	Year Ended December 31,
		2024		2023		2022
Effective interest rate:
Convertible Senior Notes Due 2025		2.1	%	2.2	%	2.2	%
Convertible Senior Notes Due 2029		2.1	%	*		*

* Not applicable as no notes were outstanding at this date.

Income Taxes - Schedule of Components of Income Tax (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Current:
Federal	$ 636	$ 308	$ 216
State	1,143	345	1,228
Foreign	2,376	1,704	298
Total current tax expense	4,155	2,357	1,742
Deferred:
Federal	0	0	0
State	0	0	0
Foreign	0	0	0
Total deferred income tax benefit	0	0	0
Income tax expense	$ 4,155	$ 2,357	$ 1,742

Business Segment and Geographic Information

12 Months Ended

Dec. 31, 2024

Segment Reporting [Abstract]

Business Segment and Geographic Information

Segment Reporting

Operating segments are identified as components of an enterprise about which discrete financial information is available for evaluation by the chief operating decision-maker (CODM) in making decisions regarding resource allocation and assessing performance. The Company is organized based on its current product portfolio, which consists primarily of insulin pumps, single-use insulin cartridges and infusion sets for the storage and delivery of insulin. The Company views its operations and manages its business as one reporting segment because key operating decisions and resource allocations are made by the CODM using consolidated financial data. Accordingly, the Company is organized as a single operating segment and therefore a single reportable segment: Insulin Pumps and Supplies.

The Company’s CODM is the Chief Executive Officer (CEO), who evaluates segment performance based on segment net income (loss) on a consolidated basis. Segment net income (loss) was consistent with the net loss amounts reported in the Company’s consolidated statement of operations and comprehensive loss for the years ended December 31, 2024, 2023, and 2022. There were no significant segment expenses that are regularly provided to the CODM other than those reported in the Company’s consolidated statement of operations and comprehensive loss for the years ended December 31, 2024, 2023, and 2022.

The Company’s CODM is provided segment assets information on a consolidated basis for the evaluation of company performance. Total segment assets were consistent with total assets reported in the Company’s consolidated balance sheets for December 31, 2024 and 2023, respectively.

Disaggregation of Revenue

Segment revenues were consistent with revenue reported in the Company’s consolidated statement of operations and comprehensive loss for the years ended December 31, 2024, 2023, and 2022. The Company primarily sells its products through national and regional distributors in the United States on a non-exclusive basis, and through distribution partners outside the United States. In the United States and Canada, the Company also uses a direct sales force. The Company disaggregates its revenue by geography, major sales channel and product as management believes these categories best depict how the nature, amount and timing of revenues and cash flows are affected by economic factors.

Revenues by Geographic Region and Customer Sales Channel

During the years ended December 31, 2024, 2023 and 2022, no individual country outside the United States generated revenue that represented more than 10% of total revenue. The table below sets forth revenues for the Company’s two primary geographical markets, based on the geographic location to which its products are shipped (in thousands):


	Year Ended December 31,
		2024		2023		2022
United States		$	672,685	$	554,878	$	588,765
Outside the United States		267,518		192,840		212,452
Total Sales		$	940,203	$	747,718	$	801,217

Revenues by Product

During the years ended December 31, 2024, 2023 and 2022, sales by product were as follows (in thousands):


	Year Ended December 31,
		2024		2023		2022
Pump		$	434,169	$	365,842	$	431,907



Supplies and other		475,785		406,983		372,859
Net revenue recognized (deferred) for Tandem Choice program		30,249		(25,107)		(3,549)
Total Sales		940,203		747,718		801,217

Sales to distributors accounted for 61%, 64%, and 65% of the Company’s total United States sales for the years ended December 31, 2024, 2023 and 2022, respectively. Sales to distributors accounted for 96%, 99%, and 96% of the Company’s total sales outside the United States for the years ended December 31, 2024, 2023 and 2022, respectively.

- Definition

The entire disclosure for reporting segments including data and tables. Reportable segments include those that meet any of the following quantitative thresholds a) it's reported revenue, including sales to external customers and intersegment sales or transfers is 10 percent or more of the combined revenue, internal and external, of all operating segments b) the absolute amount of its reported profit or loss is 10 percent or more of the greater, in absolute amount of 1) the combined reported profit of all operating segments that did not report a loss or 2) the combined reported loss of all operating segments that did report a loss c) its assets are 10 percent or more of the combined assets of all operating segments.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 55
-Paragraph 48
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482785/280-10-55-48

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 32
-Subparagraph (f)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482810/280-10-50-32

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 270
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (i)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482964/270-10-50-1

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 32
-Subparagraph (ee)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482810/280-10-50-32

Reference 5: http://fasb.org/us-gaap/role/ref/otherTransitionRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 32
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482810/280-10-50-32

Reference 6: http://www.xbrl.org/2003/role/exampleRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 55
-Paragraph 54
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482785/280-10-55-54

Reference 7: http://www.xbrl.org/2003/role/exampleRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 55
-Paragraph 47
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482785/280-10-55-47

Reference 8: http://www.xbrl.org/2003/role/exampleRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 55
-Paragraph 54
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482785/280-10-55-54

Reference 9: http://www.xbrl.org/2003/role/exampleRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 55
-Paragraph 47
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482785/280-10-55-47

Reference 10: http://www.xbrl.org/2003/role/exampleRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 55
-Paragraph 54
-Subparagraph (e)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482785/280-10-55-54

Reference 11: http://www.xbrl.org/2003/role/exampleRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 55
-Paragraph 47
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482785/280-10-55-47

Reference 12: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 22
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482810/280-10-50-22

Reference 13: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 31
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482810/280-10-50-31

Reference 14: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 34
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482810/280-10-50-34

Reference 15: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 26C
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482810/280-10-50-26C

Reference 16: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 26B
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482810/280-10-50-26B

Reference 17: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 15
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482810/280-10-50-15

Reference 18: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 42
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482810/280-10-50-42

Reference 19: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 40
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482810/280-10-50-40

Reference 20: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
-Name Accounting Standards Codification
-Publisher FASB
-URI https://asc.fasb.org/280/tableOfContent

Reference 21: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 26
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482810/280-10-50-26

Reference 22: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 41
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482810/280-10-50-41

Reference 23: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 21
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482810/280-10-50-21

Reference 24: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 21
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482810/280-10-50-21

Reference 25: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 32
-Subparagraph (e)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482810/280-10-50-32

+ Details

Leases - Lease Cost (Details) - USD ($) $ in Thousands	12 Months Ended
Leases - Lease Cost (Details) - USD ($) $ in Thousands	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Leases [Abstract]
Operating lease cost	$ 14,276	$ 15,971	$ 18,432
Short-term lease cost	87	108	142
Loss on lease termination and right-of-use asset impairment charges	0	11,224	5,699
Total lease cost	$ 14,363	$ 27,303	$ 24,273

Fourth Quarter Financial Data (Unaudited) - Basic and Diluted Net Income (Loss) Per Share (Detail) - USD ($) $ in Thousands	3 Months Ended		12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Net income - basic	$ 754
Net income - diluted	$ 754
Weighted average shares used to compute basic net loss per share (in shares)	65,939,000	65,369,000	65,451,000	64,969,000	64,146,000
Dilutive common share equivalents:
Weighted average shares used to compute diluted net loss per share (in shares)	66,157,000	65,369,000	65,451,000	64,969,000	64,146,000
Options to purchase common stock
Dilutive common share equivalents:
Common stock (in shares)	112,000
Warrants to purchase common stock
Dilutive common share equivalents:
Common stock (in shares)	59,000
Awards to be granted under the ESPP
Dilutive common share equivalents:
Awards to be granted under the ESPP (in shares)	47,000

Composition of Certain Financial Statement Items (Tables)

12 Months Ended

Dec. 31, 2024

Organization, Consolidation and Presentation of Financial Statements [Abstract]

Schedule of Accounts Receivable

Accounts receivable, net consisted of the following at December 31, 2024 and December 31, 2023 (in thousands):


	December 31,		December 31,
	2024		2023

Accounts receivable	$	121,836	$	110,453
Less: allowance for credit losses	(7,251)		(4,898)
Accounts receivable, net	$	114,585	$	105,555

Schedule of Reconciliation of Changes in the Allowance for Estimated Accounts Receivable Credit Losses

The following table provides a reconciliation of the changes in the allowance for estimated accounts receivable credit losses for the years ended December 31, 2024 and 2023 (in thousands):


	Year Ended December 31,
		2024		2023		2022
Balance at beginning of the period		$	4,898	$	4,327	$	4,249
Provision for expected credit losses		9,979		5,540		4,782
Write-offs and adjustments, net of recoveries		(7,626)		(4,969)		(4,704)
Balance at end of the period		$	7,251	$	4,898	$	4,327

Schedule of Inventories

Inventories consisted of the following at December 31, 2024 and December 31, 2023 (in thousands):


	December 31,		December 31,
	2024		2023

Raw materials	$	32,602	$	42,783
Work-in-process	33,517		44,026
Finished goods	83,493		71,128
Total inventories	$	149,612	$	157,937

Schedule of Property and Equipment

Property and equipment, net consisted of the following at December 31, 2024 and 2023 (in thousands):


	December 31,
	2024		2023
Leasehold improvements	$	37,106	$	37,565
Office furniture and equipment	11,813		11,842
Computer equipment and software	9,811		10,340
Manufacturing and scientific equipment	82,248		69,589
Total cost	140,978		129,336
Less: accumulated depreciation and amortization	(62,828)		(52,794)
Total property and equipment, net	$	78,150	$	76,542

Schedule of Intangible Assets Subject to Amortization


	December 31,
	2024		2023
Intangible assets, gross amount	$	12,502	$	12,502
Accumulated amortization	(11,577)		(9,726)
Intangible assets, net	$	925	$	2,776
Weighted average remaining amortization period (in months)	6		18

Business Segment and Geographic Information - Geographical Markets (Details) - USD ($) $ in Thousands	3 Months Ended		12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Disaggregation of Revenue [Line Items]
Total Sales	$ 282,648	$ 196,796	$ 940,203	$ 747,718	$ 801,217
United States
Disaggregation of Revenue [Line Items]
Total Sales			672,685	554,878	588,765
Outside the United States
Disaggregation of Revenue [Line Items]
Total Sales			$ 267,518	$ 192,840	$ 212,452

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References + Details

- Definition

Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 41
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482810/280-10-50-41

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 270
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (i)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482964/270-10-50-1

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 32
-Subparagraph (ee)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482810/280-10-50-32

Reference 4: http://fasb.org/us-gaap/role/ref/otherTransitionRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 32
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482810/280-10-50-32

Reference 5: http://fasb.org/us-gaap/role/ref/otherTransitionRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 32
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482810/280-10-50-32

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Topic 924
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SAB Topic 11.L)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479941/924-10-S99-1

Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 5
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479806/606-10-50-5

Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 30
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482810/280-10-50-30

Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 42
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482810/280-10-50-42

Reference 10: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 22
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482810/280-10-50-22

Reference 11: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 40
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482810/280-10-50-40

Reference 12: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 22
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482810/280-10-50-22

Reference 13: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 4
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479806/606-10-50-4

+ Details

Income Taxes - Additional Information (Details) - USD ($)	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Operating Loss Carryforwards [Line Items]
Valuation allowance	$ 210,363,000	$ 190,664,000
Net deferred tax assets	0	0
Unrecognized tax benefits	24,900,000	19,200,000
Accrual interest and penalties	$ 0	0	$ 0
Minimum
Operating Loss Carryforwards [Line Items]
Income tax realization	50.00%
Capillary Biomedical
Operating Loss Carryforwards [Line Items]
Deferred tax assets acquired			$ 7,800,000
Net deferred tax assets		$ 5,000,000
CALIFORNIA
Operating Loss Carryforwards [Line Items]
NOL carryforwards subject to expiration	$ 182,400,000
Federal
Operating Loss Carryforwards [Line Items]
NOL carry forwards amount	96,500,000
NOL carryforwards not subject to expiration	13,200,000
NOL carryforwards subject to expiration	83,200,000
Federal \| Research Tax Credit Carryforward
Operating Loss Carryforwards [Line Items]
Tax credit carryforward, amount	30,700,000
State and Local
Operating Loss Carryforwards [Line Items]
NOL carry forwards amount	248,000,000.0
Foreign
Operating Loss Carryforwards [Line Items]
NOL carryforwards subject to expiration	43,300,000
CALIFORNIA \| Research Tax Credit Carryforward
Operating Loss Carryforwards [Line Items]
Tax credit carryforward, amount	$ 29,300,000

Composition of Certain Financial Statement Items - Reconciliation of Change in Estimated Allowance for Doubtful Accounts (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Allowance for doubtful accounts
Balance at beginning of the period	$ 4,898	$ 4,327	$ 4,249
Provision for expected credit losses	9,979	5,540	4,782
Write-offs and adjustments, net of recoveries	(7,626)	(4,969)	(4,704)
Balance at end of the period	$ 7,251	$ 4,898	$ 4,327

Stockholders' Equity - Allocation of Stock-Based Compensation Expense (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation expense	$ 101,383	$ 88,076	$ 84,918
Cost of sales
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation expense	7,361	6,212	7,685
Selling, general and administrative
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation expense	62,794	56,303	57,196
Research and development
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation expense	$ 31,228	$ 25,561	$ 20,037

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section 35
-Paragraph 1D
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480483/718-10-35-1D

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section 35
-Paragraph 3
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480483/718-10-35-3

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (a)(1)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480429/718-10-50-2

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (a)(2)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480429/718-10-50-2

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (a)(3)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480429/718-10-50-2

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(i)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480429/718-10-50-2

Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(ii)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480429/718-10-50-2

Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(iii)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480429/718-10-50-2

Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(iv)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480429/718-10-50-2

Reference 10: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(iv)(01)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480429/718-10-50-2

Reference 11: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(iv)(02)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480429/718-10-50-2

Reference 12: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(iv)(03)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480429/718-10-50-2

Reference 13: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(iv)(04)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480429/718-10-50-2

Reference 14: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (c)(2)(i)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480429/718-10-50-2

Reference 15: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (c)(2)(ii)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480429/718-10-50-2

Reference 16: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (c)(2)(iii)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480429/718-10-50-2

Reference 17: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (c)(2)(iii)(01)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480429/718-10-50-2

Reference 18: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (c)(2)(iii)(02)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480429/718-10-50-2

Reference 19: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (c)(2)(iii)(03)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480429/718-10-50-2

Reference 20: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (d)(1)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480429/718-10-50-2

Reference 21: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (d)(2)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480429/718-10-50-2

Reference 22: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (e)(1)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480429/718-10-50-2

Reference 23: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (e)(2)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480429/718-10-50-2

Reference 24: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (f)(2)(i)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480429/718-10-50-2

Reference 25: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (f)(2)(ii)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480429/718-10-50-2

Reference 26: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (f)(2)(iii)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480429/718-10-50-2

Reference 27: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (f)(2)(iv)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480429/718-10-50-2

Reference 28: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (f)(2)(v)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480429/718-10-50-2

+ Details

Debt - Components of Convertible Note (Details) - USD ($)	Dec. 31, 2024	Mar. 31, 2024	Mar. 08, 2024	Dec. 31, 2023	May 31, 2020
Debt Instrument [Line Items]
Unamortized debt issuance costs	$ (9,400,000)
Less: current portion	(40,670,000)			$ 0
Long-term senior convertible notes	308,266,000			285,035,000
Convertible Senior Notes \| Convertible Senior Notes Due 2025
Debt Instrument [Line Items]
Principal amount:	40,760,000			287,500,000	$ 287,500,000
Convertible Senior Notes \| Convertible Senior Notes Due 2029
Debt Instrument [Line Items]
Principal amount:	316,250,000	$ 316,300,000	$ 316,300,000
Convertible Senior Notes \| Convertible Senior Notes
Debt Instrument [Line Items]
Principal amount:	357,010,000			287,500,000
Unamortized debt issuance costs	(8,074,000)			(2,465,000)
Total debt, net	$ 348,936,000			$ 285,035,000

Fair Value Measurements - Estimated the Fair Value (Details) - Level 2 - Convertible Senior Notes - USD ($) $ in Thousands	Dec. 31, 2024	Dec. 31, 2023
Convertible Senior Notes due 2025
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Convertible senior notes, fair value	$ 39,130	$ 271,688
Convertible Senior Notes due 2029
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Convertible senior notes, fair value	407,752
Convertible Senior Notes
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Convertible senior notes, fair value	$ 446,882	$ 271,688

Leases - Lease Payments (Details) - USD ($) $ in Thousands	12 Months Ended
Leases - Lease Payments (Details) - USD ($) $ in Thousands	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Leases [Abstract]
Operating lease payments	$ 17,941	$ 13,864	$ 11,960
Operating lease termination payments	0	0	4,769
Total cash payments	$ 17,941	$ 13,864	$ 16,729

Summary of Significant Accounting Policies

12 Months Ended

Dec. 31, 2024

Accounting Policies [Abstract]

Summary of Significant Accounting Policies

There have been no material changes to the Company’s significant accounting policies during the year ended December 31, 2024, except for adding the accounting policy for equity method investments, which is included herein.

Use of Estimates

The preparation of the consolidated financial statements in conformity with U.S. GAAP requires management to make estimates and judgments that affect the reported amounts of assets, liabilities, revenues and expenses and the disclosure of contingent assets and liabilities in the Company’s consolidated financial statements and accompanying notes as of the date of the consolidated financial statements. Some of those judgments can be subjective and complex, and therefore, actual results could differ materially from those estimates under different assumptions or conditions.

Cash Equivalents

The Company considers all highly liquid investments with a maturity of three months or less from the date of purchase and that can be liquidated without prior notice or penalty to be cash equivalents.

Short-Term Investments

The Company’s short-term investments are classified as available-for-sale securities. Such securities are carried at fair value as determined by prices for identical or similar securities at the balance sheet date. The Company’s short-term investments consist of Level 1 and Level 2 financial instruments in the fair value hierarchy. The net unrealized gains or losses on available-for-sale securities that are not related to credit factors are reported as a component of other comprehensive income (loss) within the statements of operations and accumulated other comprehensive income (loss) as a separate component of stockholders’ equity on the consolidated balance sheets. The Company determines realized gains or losses on the sale of available-for-sale securities using the specific identification method and includes net realized gains and losses as a component of other income or expense within the consolidated statements of operations.

The Company reviews its available-for-sale debt securities for credit losses quarterly, considering a variety of factors, including the significance of the decline in value as compared to the amortized cost basis; underlying factors contributing to a decline in the prices of securities in a single asset class; the security’s relative performance versus its peers, sector or asset class; the market and economy in general; views of external investment managers; news or financial information that has been released specific to the investee; and the outlook for the overall industry in which the investee operates. Losses on available-for-sale debt securities as a result of credit factors are recognized by recording an impairment loss as a component of other income or expense within the consolidated statements of operations and a corresponding allowance for credit losses. The Company has not recognized any impairment losses related to its short-term investments during the years ended December 31, 2024, 2023 and 2022.

Accounts Receivable

The Company grants credit to various customers in the ordinary course of business and is paid directly by customers who use its products, distributors and third-party insurance payors. The Company maintains an allowance for its current estimate of expected credit losses. Provisions for expected credit losses are estimated based on historical experience, assessment of specific customer-related risks, review of outstanding invoices, forecasts about the future, and various other assumptions and estimates that are believed to be reasonable under the circumstances, including changes to credit risks as a result of recessionary concerns, changes in discretionary spending, increased interest rates, and other macroeconomic factors. Uncollectible accounts are written off against the allowance after appropriate collection efforts have been exhausted and when it is deemed that a balance is uncollectible.

Concentration of Credit Risk

Financial instruments that potentially subject the Company to concentrations of credit risk consist primarily of cash, cash equivalents, short-term investments and accounts receivable. The Company maintains deposit accounts in federally insured financial institutions in excess of federally insured limits. The Company also maintains investments in money market funds that are not federally insured. Additionally, the Company has established guidelines regarding investment instruments and their maturities, which are designed to maintain preservation of principal and liquidity.

The following table summarizes the percentages of total sales and accounts receivable, net for customers who accounted for 10% or more of the respective amounts for the periods presented:


	Total Sales						Accounts Receivable, net
	Year Ended December 31,						December 31,
	2024		2023		2022		2024		2023
Distributor A	11.2	%	12.2	%	11.6	%	11.1	%	10.0	%
Distributor B	*		*		*		*		10.5	%
Distributor C	*		*		*		11.8	%	10.6	%
Distributor D	11.5	%	10.8	%	14.4	%	11.2	%	11.5	%

* Amount related to the respective customer represented less than 10% for the period presented.

Valuation of Inventories

Inventories are valued at the lower of cost or net realizable value, determined by the first-in, first-out method. Inventory is recorded using standard cost, including material, labor and overhead costs. The Company periodically reviews inventories for potential impairment and adjusts inventory for potentially excess or obsolete goods to state inventories at their net realizable value. Factors influencing these adjustments include quantities on hand and firm purchase commitments, expectations of future use, judgments based on quality control testing data and assessments of the likelihood of scrapping or obsoleting certain inventories based on future demand for its products and market conditions.

Long-Lived Assets

Property and Equipment

Property and equipment, which primarily consist of office furniture and equipment, manufacturing equipment, scientific equipment, computer equipment, and leasehold improvements, are stated at cost, less accumulated depreciation. Property and equipment are depreciated over the estimated useful lives of the assets, generally three to seven years, using the straight-line method. Leasehold improvements and related equipment are amortized over the lesser of the estimated useful lives of the assets or the remaining lease term, unless there is a transfer of title or purchase option that is reasonably certain to be exercised. Maintenance and repair costs are expensed as incurred.

Operating Lease Right-of-Use Assets and Liabilities

Operating lease right-of-use assets represent the Company’s right to use an underlying asset for the lease term and lease liabilities represent its obligation to make lease payments arising from the lease. Operating lease right-of-use assets and liabilities are recognized when the Company takes possession of the leased property (Commencement Date) based on the present value of lease payments over the lease term. For lease agreements that contain lease and non-lease components, the Company accounts for both of those components as a single lease component. Rent expense on noncancelable leases containing known future scheduled rent increases is recorded on a straight-line basis over the term of the respective leases beginning on the Commencement Date. The difference between rent expense and rent paid is accounted for as a component of operating lease right-of-use assets on the Company’s consolidated balance sheets. Landlord improvement allowances and other similar lease incentives are recorded as a reduction of the right-of-use leased assets, and are amortized on a straight-line basis as a reduction to operating lease costs.

Intangible Assets Subject to Amortization

Finite-lived intangible assets are recorded at cost, net of accumulated amortization and, if applicable, impairment charges. Amortization of finite-lived intangible assets is recognized over their estimated useful lives on a straight-line basis.

Impairment of Long-Lived Assets

Long-lived assets, such as property and equipment, right-of-use lease assets, and acquired intangible assets subject to amortization, are reviewed for impairment whenever events or changes in circumstances indicate that the carrying amount of an asset may not be recoverable. If circumstances require a long-lived asset or asset group be tested for possible impairment, the Company first compares undiscounted cash flows expected to be generated by that asset or asset group to its carrying amount. If the carrying amount of the long-lived asset or asset group is not recoverable on an undiscounted cash flow basis, an impairment is recognized to the extent that the carrying amount exceeds its fair value. Fair value is determined using unobservable (Level 3) inputs, including discounted cash flow models, future estimated sublease income, and third-party independent appraisals, as considered necessary. There is uncertainty in the projected undiscounted future cash flows used in the Company’s impairment review analysis, which requires the use of estimates and assumptions. If actual performance does not achieve the projections, or if the assumptions used change in the future, the Company may be required to recognize additional impairment charges in future periods. Other than the impairment of operating lease right-of-use assets and related leasehold improvements and furniture and fixtures recognized in 2023 and 2022 (see Note 6, “Leases”), there were no impairments of long-lived assets, including acquired intangible assets, during the years ended December 31, 2024, 2023 and 2022.

Strategic Investments

The Company measures strategic investments at cost minus impairment, if any, adjusted for changes in observable prices. Strategic investments are reviewed, on an individual basis, for impairment whenever significant events or changes in circumstances indicate that the carrying amount of the investment might not be recoverable.

The Company held strategic equity investments totaling zero and $10.1 million in private investee companies at December 31, 2024 and December 31, 2023, respectively. In November 2024, the Company invested an additional $46.4 million cash in one of its private company investees, resulting in a change to equity method accounting, described below. During the year ended December 31, 2024, the Company also recorded an impairment charge of $2.0 million related to one of its strategic investments in a private investee company. The Company did not record any impairment charges related to its strategic investments during the years ended December 31, 2023 and 2022. The strategic investments were included as a component of other long-term assets on the consolidated balance sheet.

From November 2023 to June 2024, the company held a strategic investment balance of $22.2 million in the form of subordinated convertible notes of one private investee company. The subordinated notes were converted into equity of the private investee company at final maturity, which occurred in June 2024.

Equity Method Investments

The Company held equity method investments of $74.5 million at December 31, 2024. We use the equity method to account for investments in companies if our investment provides us with the ability to exercise significant influence but not control over the operating and financial policies of the investee. The Company assesses significant influence by considering various factors, including the nature and magnitude of the investment, voting rights held and participation in the governance of the investee, if any. The Company may also consider additional relevant factors, such as the presence of other business relationships.

In November 2024, the Company invested an additional $46.4 million cash in one of its private investee companies that was previously accounted for as a strategic investment at cost. As a result of the additional investment, the Company owned more than 20% of the private investee company’s outstanding equity and held significant influence but not control over the private investee company’s activities. As a result, the investment was accounted for using the equity method following the November 2024 transaction date.

Our consolidated net loss included our Company’s proportionate share of the net loss of our equity method investee, which was a loss of $2.1 for the year ended December 31, 2024. For the years ended December 31, 2023 and 2022, the Company did not hold any equity method investments and therefore did not recognize a share of net income or loss from any equity method investments.

Revenue Recognition

Revenue is generated primarily from sales of insulin pumps, single-use insulin cartridges and infusion sets to individual customers with third-party insurance coverage and through a network of distributors that resell the products to insulin-dependent diabetes customers. The Company recognizes revenue when it transfers control of the promised goods or services to customers in an amount that reflects the consideration to which the Company expects to be entitled in exchange for those goods or services, net of estimated rebates and returns.

Revenue Recognition for Arrangements with Multiple Performance Obligations

The Company considers the individual deliverables in its product offerings to be separate performance obligations. The transaction price is determined based on the consideration expected to be received, based either on the stated value in contractual arrangements or the estimated cash to be collected in non-contracted arrangements. The Company allocates the consideration to the individual performance obligations and recognizes the consideration based on when the performance obligation is satisfied, considering whether or not this occurs at a point in time or over time. Generally, insulin pumps, cartridges, infusion sets, and accessories are deemed performance obligations that are satisfied at a point in time when the customer obtains control of the promised good, which typically is upon shipment for our distributor arrangements and upon receipt for sales directly to individual customers. Complementary products, such as the Company’s data management and software update platforms, are considered distinct performance obligations that are satisfied over time, as access and support for these products is provided throughout the typical four-year warranty period of the insulin pumps. Accordingly, revenue related to the complementary products is deferred and recognized over a four-year period. Where there is no standalone value for the complementary product, the Company determines its value by applying the expected cost plus a margin approach and then allocates the residual to the insulin pumps.

Revenue Recognition for Tandem Choice Program

In September 2022, the Company launched a technology access program referred to as Tandem Choice, that provided eligible, in-warranty t:slim X2 customers in the United States with the flexibility to obtain the newest hardware platform, Tandem Mobi, once commercially available. Participating customers had the right to purchase the alternative Tandem pump for a fee, referred to as a choice right. The Company determined that the program created a material right for which a portion of each t:slim X2 pump sales transaction price was allocated and deferred.

The Company determined that the ability for a customer to upgrade to a new technology represents a material right because the pricing inherent in such option provided the customer with a discount that is incremental to the range of discounts that would otherwise be granted for the related goods and services to comparable customers. The standalone selling price for the choice right was estimated based on the adjusted market assessment approach and contemplated the likelihood that the respective option will be exercised.

The Company began selling Tandem Mobi insulin pumps in the first quarter of 2024 and eligibility for the Tandem Choice program ended in February 2024. Consequently, the Company ceased allocating and deferring a portion of the transaction price for the material right for pumps sold after that date. Eligible customers who purchased a t:slim X2 insulin pump during the program period had until December 31, 2024 to exercise the option to switch to the Tandem Mobi for a stated fee.

The Company recognized the deferred sales when the obligations under the Tandem Choice program were satisfied. If a customer elected to participate in the program, the Company recognized upgrade fees received, and the associated cost of goods sold at the time of fulfillment. Substantially all of the remaining deferrals were recognized at program expiration on December 31, 2024. For the year ended December 31, 2024, the Company recognized net revenue of $30.2 million as a result of the Tandem Choice program.

Sales Rebates

The Company is subject to certain rebates on pricing programs with managed care organizations, such as governmental and third-party commercial payors. The Company estimates provisions for rebates based on contractual arrangements, estimates of products sold subject to rebate, known events or trends and channel inventory data. Estimated sales rebates included in other long-term liabilities have an estimated payment due date beyond twelve months from the balance sheet date. Accordingly, actual rebates paid may differ from estimated amounts recorded in the accompanying consolidated financial statements.

As of December 31, 2024 and December 31, 2023, total estimated sales rebates were included in the following consolidated balance sheet accounts (in thousands):


	December 31, 2024		December 31, 2023
Other current liabilities	$	2,229	$	505
Other long-term liabilities	7,167		8,042
Total sales rebate	$	9,396	$	8,547

Sales Returns

The Company offers a 90-day right of return to customers in the United States and Canada from the date of shipment of its insulin pumps, provided a physician’s confirmation of the medical reason for the return is received. Estimated allowances for sales returns are based on historical returned quantities as compared to pump shipments in those same periods of return, adjusted for known or expected changes in the marketplace when appropriate. The amounts recorded in deferred revenue on the Company’s consolidated balance sheets for allowances for sales returns were not material for the periods presented. Actual product returns have not differed materially from estimated amounts recorded in the accompanying consolidated financial statements.

Warranty Reserve

The Company generally provides a four-year warranty on its insulin pumps to end-user customers and may replace any pumps that do not function as intended in accordance with the product specifications within the warranty period. In addition, the Company offers a six-month warranty on single-use insulin cartridges and infusion sets. Estimated warranty costs are recorded at the time of shipment, and the Company reevaluates the estimate of the warranty reserve obligation at each reporting period. Warranty costs are primarily estimated based on the current expected product replacement cost and expected replacement rates using historical experience. Returned insulin pumps may be refurbished and redeployed.

Experience has shown that initial data for any new pump version or pump platform may be insufficient. Therefore, the Company relies on long-term historical replacement data from existing platforms until sufficient data is available. As actual experience accumulates, the Company adjusts its warranty reserve estimate accordingly. In addition, the availability of replacement data may differ by country due to local compliance and privacy regulations, which may require the Company to estimate its warranty liability using available information or data from similar markets. The Company may make further adjustments to the warranty reserve when appropriate, considering revised expectations of product performance based on enhanced hardware, or new features and capabilities that may become available through Tandem Device Updater. Warranty expense is recorded as a component of cost of sales in the consolidated statements of operations.

The following table provides a reconciliation of the changes in product warranty liabilities for the years ended December 31, 2024, 2023 and 2022 (in thousands):


	Year Ended December 31,
		2024		2023		2022
Balance at beginning of the period		$	37,173	$	36,537	$	30,401
Provision for warranties issued during the period		48,938		35,690		32,699
Settlements made during the period		(36,632)		(32,617)		(25,447)
Increases (decreases) in warranty estimates		1,929		(2,437)		(1,116)
Balance at end of the period		$	51,408	$	37,173	$	36,537

As of December 31, 2024 and December 31, 2023, total product warranty reserves were included in the following consolidated balance sheet accounts (in thousands):


	December 31, 2024		December 31, 2023

Other current liabilities	$	31,048	$	18,135
Other long-term liabilities	20,360		19,038
Total warranty reserve	$	51,408	$	37,173

Stock-Based Compensation

Stock-based compensation cost is measured at the grant date based on the estimated fair value of the award, and the portion that is ultimately expected to vest is recognized as compensation expense over the requisite service period on a straight-line basis. The Company estimates the fair value of stock options issued under the Company’s stock incentive plans, and the fair value of employee purchase rights under the Company’s Employee Stock Purchase Plan (ESPP) using the Black-Scholes option pricing model on the date of grant. The Black-Scholes option pricing model requires the use of assumptions about a number of variables, including stock price volatility, expected term, dividend yield and risk-free interest rate (see Note 8, “Stockholders’ Equity”). The fair value of restricted stock unit (RSU) awards issued under the Company’s stock incentive plans that vest solely based on service, is estimated based on the fair market value of the underlying stock on the date of grant. The fair value of RSU awards that vest based upon the Company’s actual performance relative to predefined performance metrics and the awardee’s continuing service through the measurement date is generally estimated based on the fair market value of the underlying stock on the date of grant and the probability that the specified performance criteria will be met. At each reporting period, the Company reassesses the probability of the achievement of such performance metrics. Any expense change resulting from an adjustment in the estimated shares to be released is recorded in the period of adjustment.

Shipping and Handling Expenses

Shipping and handling expenses associated with product delivery are included within cost of sales in the Company’s statements of operations. Amounts billed to a customer for shipping and handling are reported as revenues.

Research and Development Costs

All research and development costs are charged to expense as incurred. Such costs include personnel-related costs, including stock-based compensation, supplies, license fees, development prototypes, outside design and testing services, depreciation, allocated facilities and information services, clinical trial costs, milestone payments under the Company’s licensing, development and commercialization agreements, and other indirect costs.

Acquired In-Process Research and Development Expenses

Acquired in-process research and development (IPR&D) expenses reflect the costs of externally developed IPR&D projects acquired directly in a transaction other than a business combination that do not have an alternative future use, including the initial costs of rights to IPR&D projects. The acquired IPR&D is expensed on acquisition date. Future costs to develop these IPR&D projects are recorded in research and development expenses on the consolidated statements of operations as incurred.

Income Taxes

The Company uses the asset and liability method of accounting for income taxes. Deferred tax assets or liabilities are recognized based on the temporary differences between financial statement and income tax bases of assets and liabilities using enacted tax rates in effect for the years in which the differences are expected to reverse. Tax law and rate changes are reflected in income in the period such changes are enacted. A valuation allowance is recorded when it is more likely than not that some of the deferred tax assets will not be realized. The evaluation of the need for a valuation allowance is performed on a jurisdiction-by-jurisdiction basis, and includes a review of all available positive and negative evidence. Factors reviewed include projections of pre-tax book income for the foreseeable future, determination of cumulative pre-tax book income after permanent differences, earnings history, and reliability of forecasting. The Company will continue to assess the need for a valuation allowance on its deferred tax assets by evaluating both positive and negative evidence that may exist. Any adjustment to the net deferred tax asset valuation allowance would be recorded in the consolidated statement of operations for the period that the adjustment is determined to be required.

Comprehensive Loss

All components of comprehensive loss, including net loss, are reported in the consolidated financial statements in the period in which they are recognized. Comprehensive loss is defined as the change in equity during a period from transactions and other events and circumstances from non-owner sources, including unrealized gains and losses on marketable securities and foreign currency translation adjustments.

Net Loss Per Share

Basic net loss per share is calculated by dividing the net loss by the weighted average number of common shares outstanding for the period, without consideration for common stock equivalents. Diluted net loss per share reflects the potential dilution that would occur if securities exercisable for or convertible into common stock were exercised for or converted into common stock. Dilutive common share equivalents are comprised of stock options and unvested RSUs outstanding under the Company’s stock incentive plans, potential awards to be granted pursuant to the ESPP, and common stock warrants, each calculated using the treasury stock method, and shares issuable upon conversion of the convertible senior notes calculated using the if-converted method.

For the years ended December 31, 2024, 2023, and 2022, there was no difference in the weighted average number of shares used to calculate basic and diluted net loss per share due to the Company’s net loss position in each period.

Potentially dilutive securities outstanding and not included in the calculation of diluted net loss per share (because inclusion would be anti-dilutive) are as follows (in thousands, in common stock equivalent shares):


	Year Ended December 31,
		2024	2023	2022
Options to purchase common stock		124	135	1,138
Unvested restricted stock units		2,858	2,089	1,118
Warrants to purchase common stock		194	194	194
Awards granted under the ESPP		58	14	8
Convertible senior notes (if-converted)		8,202	2,554	2,554
		11,436	4,986	5,012

Recently Issued Accounting Pronouncements

In November 2023, the FASB issued ASU 2023-07 to improve the information that a public entity discloses about reportable segments and to address investor requests for more information about reportable segment expenses. The pronouncement requires a public entity to report a measure of segment profit or loss that the chief operating decision maker (CODM) uses to assess segment performance and make decisions about allocating resources. ASU 2023-07 also requires other specified segment items and amounts, such as depreciation, amortization, and depletion expense, to be disclosed under certain circumstances. The amendments in ASU 2023-07 are effective for fiscal years beginning after December 15, 2023 and interim periods within fiscal years beginning after December 15, 2024, adopted retrospectively. The Company’s adoption of ASU 2023-07 did not have a material impact on the Company’s consolidated financial statements or disclosures.

Accounting Pronouncements Issued and Not Yet Adopted

In November 2024, the FASB issued ASU 2024-03 Income Statement–Reporting Comprehensive Income–Expense Disaggregation Disclosures (Subtopic 220-40): Disaggregation of Income Statement Expenses (ASU 2024-03), which requires entities to disclose information about purchases of inventory, employee compensation, and intangible asset amortization in each income statement line item that contains those expenses. ASU 2024-03 is effective for annual reporting periods beginning after December 15, 2026 and interim reporting periods beginning after December 15, 2027. Early adoption is permitted. The Company is currently evaluating ASU 2024-03 to determine the impact it may have on its consolidated financial statements.

In December 2023, the FASB issued ASU 2023-09 Income Taxes (Topic 740): Improvements to Income Tax Disclosures, which requires the Company to disclose disaggregated jurisdictional and categorical information for the tax rate reconciliation, income taxes paid and other income tax related amounts. The guidance is effective for annual periods beginning after December 15, 2024, with early adoption permitted. The Company is currently evaluating ASU 2023-09 to determine the impact it may have on its consolidated financial statements.

Debt - Effective Interest Rates of Convertible Senior Notes (Details) - Convertible Senior Notes	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Convertible Senior Notes Due 2025
Debt Instrument [Line Items]
Effective interest rate	2.10%	2.20%	2.20%
Convertible Senior Notes Due 2029
Debt Instrument [Line Items]
Effective interest rate	2.10%

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 835
-SubTopic 30
-Name Accounting Standards Codification
-Section 55
-Paragraph 8
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482949/835-30-55-8

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 235
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08(f))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480678/235-10-S99-1

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 235
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 3
-Subparagraph (SX 210.12-04(a))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480678/235-10-S99-3

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1B
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481139/470-20-50-1B

Reference 5: http://www.xbrl.org/2003/role/exampleRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 55
-Paragraph 69B
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481568/470-20-55-69B

Reference 6: http://www.xbrl.org/2003/role/exampleRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 55
-Paragraph 69C
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481568/470-20-55-69C

Reference 7: http://www.xbrl.org/2003/role/exampleRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 55
-Paragraph 69E
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481568/470-20-55-69E

Reference 8: http://www.xbrl.org/2003/role/exampleRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 55
-Paragraph 69F
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481568/470-20-55-69F

Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1B
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481139/470-20-50-1B

Reference 10: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1B
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481139/470-20-50-1B

Reference 11: http://www.xbrl.org/2003/role/exampleRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1B
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481139/470-20-50-1B

Reference 12: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1B
-Subparagraph (e)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481139/470-20-50-1B

Reference 13: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1B
-Subparagraph (f)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481139/470-20-50-1B

Reference 14: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1B
-Subparagraph (h)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481139/470-20-50-1B

Reference 15: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1D
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481139/470-20-50-1D

Reference 16: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1D
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481139/470-20-50-1D

Reference 17: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1D
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481139/470-20-50-1D

Reference 18: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1E
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481139/470-20-50-1E

Reference 19: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1E
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481139/470-20-50-1E

Reference 20: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1E
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481139/470-20-50-1E

Reference 21: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1F
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481139/470-20-50-1F

Reference 22: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1F
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481139/470-20-50-1F

Reference 23: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1F
-Subparagraph (b)(1)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481139/470-20-50-1F

Reference 24: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1F
-Subparagraph (b)(2)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481139/470-20-50-1F

Reference 25: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1I
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481139/470-20-50-1I

Reference 26: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 835
-SubTopic 30
-Name Accounting Standards Codification
-Section 45
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482925/835-30-45-2

Reference 27: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 835
-SubTopic 30
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482900/835-30-50-1

+ Details

Acquisitions	12 Months Ended
Acquisitions	Dec. 31, 2024
Business Combination, Asset Acquisition, and Joint Venture Formation [Abstract]
Acquisitions	Acquisitions AMF Medical Acquisition On December 10, 2022, the Company entered into a Share Purchase Agreement (Purchase Agreement) to acquire all of the registered shares of AMF Medical (Original Transaction). AMF Medical is the original developer of the Sigi Patch Pump, which continued to be under development and was not yet commercially available as of December 31, 2024. On January 19, 2023, the Company completed the acquisition of AMF Medical under the terms of the Purchase Agreement. The total aggregate consideration for the Original Transaction included a previous strategic investment of Swiss Francs (CHF) 8.0 million made in the third quarter of 2022, a cash payment of CHF 62.4 million paid at the closing of the Transaction, and additional contingent earnout payments of up to CHF 129.6 million. The contingent earnout payments were to become payable upon the achievement of certain milestones, and were comprised of up to CHF 38.4 million upon the successful completion of key development milestones over the two years following the closing date of the Transaction, and up to CHF 91.2 million upon obtaining regulatory clearance from the FDA of an automated controller enabled (ACE) pump. The contingent consideration was to be recognized as each contingency was resolved and the respective consideration was paid or became payable. The transaction was accounted for as an asset acquisition as substantially all the value of the gross assets was concentrated in a single asset. The Company recorded a $78.8 million charge in 2023 representing the value of acquired in-process research and development assets with no alternative future use, and acquisition related expenses, on its consolidated statements of operations in acquired in-process research and development expenses. In January 2025, the Company entered into a revised agreement that removed contingent liabilities previously outlined in the Original Transaction. The Company agreed to pay CHF 40 million in January 2025 and a final payment of CHF 28 million in October 2025. All other payments outlined in the Original Transaction were removed based on the revised agreement. The amounts due to be paid were recorded as a short-term accrued liability in the first quarter of 2025. Capillary Biomedical Acquisition On July 21, 2022, the Company acquired Capillary Biomedical, Inc. (Capillary Biomedical), an infusion set developer, for total cash consideration of $24.7 million, and the assumption of $4.7 million of long-term debt (see Note 7, “Debt”). Capillary Biomedical’s extended-wear infusion set technology is currently in development and is not yet commercially available. The transaction was accounted for as an asset acquisition as substantially all the value of the gross assets was concentrated in a single asset. The Company recorded a $31.0 million charge in 2022 representing the value of acquired in-process research and development assets with no alternative future use, and acquisition related expenses, on its consolidated statements of operations in acquired in-process research and development expenses.

CONSOLIDATED STATEMENTS OF STOCKHOLDERS’ EQUITY - USD ($) $ in Thousands	Total	Common Stock	Additional Paid-in Capital	Accumulated Other Comprehensive Income (Loss)	Accumulated Deficit
Beginning balance (in shares) at Dec. 31, 2021		63,833,000
Beginning balance at Dec. 31, 2021	$ 433,112	$ 64	$ 1,068,259	$ (616)	$ (634,595)
Increase (Decrease) in Stockholders' Equity
Exercise of stock options (in shares)	280,275	280,000
Exercise of stock options	$ 9,131	$ 1	9,130
Vesting of restricted stock units, net of shares withheld for taxes (in shares)		131,000
Vesting of restricted stock units, net of shares withheld for taxes	(4,374)		(4,374)
Issuance of common stock under Employee Stock Purchase Plan (in shares)		263,000
Issuance of common stock under Employee Stock Purchase Plan	12,713		12,713
Exercise of common stock warrants (in shares)		6,000
Exercise of common stock warrants	83		83
Stock-based compensation expense	85,077		85,077
Unrealized gain on short-term investments	(2,233)			(2,233)
Foreign currency translation gains (losses)	1,032			1,032
Net loss	(94,594)				(94,594)
Ending balance (in shares) at Dec. 31, 2022		64,513,000
Ending Balance at Dec. 31, 2022	$ 439,947	$ 65	1,170,888	(1,817)	(729,189)
Increase (Decrease) in Stockholders' Equity
Exercise of stock options (in shares)	72,536	73,000
Exercise of stock options	$ 1,295		1,295
Vesting of restricted stock units, net of shares withheld for taxes (in shares)		467,000
Vesting of restricted stock units, net of shares withheld for taxes	(7,790)		(7,790)
Issuance of common stock under Employee Stock Purchase Plan (in shares)		499,000
Issuance of common stock under Employee Stock Purchase Plan	10,679	$ 1	10,678
Stock-based compensation expense	88,926		88,926
Unrealized gain on short-term investments	3,606			3,606
Foreign currency translation gains (losses)	(420)			(420)
Net loss	(222,611)				(222,611)
Ending balance (in shares) at Dec. 31, 2023		65,552,000
Ending Balance at Dec. 31, 2023	313,632	$ 66	1,263,997	1,369	(951,800)
Increase (Decrease) in Stockholders' Equity
Stock repurchase and retirement of shares (in shares)		(1,107,000)
Stock repurchase and retirement of shares	$ (30,000)	$ (1)	(29,999)
Exercise of stock options (in shares)	112,171	112,000
Exercise of stock options	$ 2,233		2,233
Vesting of restricted stock units, net of shares withheld for taxes (in shares)		937,000
Vesting of restricted stock units, net of shares withheld for taxes	(21,159)	$ 1	(21,160)
Issuance of common stock under Employee Stock Purchase Plan (in shares)		770,000
Issuance of common stock under Employee Stock Purchase Plan	12,195	$ 0	12,195
Stock-based compensation expense	101,167		101,167
Purchase of capped call options related to convertible notes due 2029	(15,813)		(15,813)
Unwind of capped call options related to convertible notes due 2025	184		184
Unrealized gain on short-term investments	(311)			(311)
Foreign currency translation gains (losses)	(3,005)			(3,005)
Net loss	(96,025)				(96,025)
Ending balance (in shares) at Dec. 31, 2024		66,264,000
Ending Balance at Dec. 31, 2024	$ 263,098	$ 66	$ 1,312,804	$ (1,947)	$ (1,047,825)

Business Segment and Geographic Information - Revenues by Product (Details) - USD ($) $ in Thousands	3 Months Ended		12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Disaggregation of Revenue [Line Items]
Total Sales	$ 282,648	$ 196,796	$ 940,203	$ 747,718	$ 801,217
Pump
Disaggregation of Revenue [Line Items]
Total Sales			434,169	365,842	431,907
Supplies and other
Disaggregation of Revenue [Line Items]
Total Sales			475,785	406,983	372,859
Net revenue recognized (deferred) for Tandem Choice program
Disaggregation of Revenue [Line Items]
Total Sales			$ 30,249	$ (25,107)	$ (3,549)

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References + Details

- Definition

+ References

+ Details

Insider Trading Arrangements	3 Months Ended
Insider Trading Arrangements	Dec. 31, 2024
Trading Arrangements, by Individual
Rule 10b5-1 Arrangement Adopted	false
Non-Rule 10b5-1 Arrangement Adopted	false
Rule 10b5-1 Arrangement Terminated	false
Non-Rule 10b5-1 Arrangement Terminated	false

CONSOLIDATED STATEMENTS OF OPERATIONS AND COMPREHENSIVE LOSS - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Income Statement [Abstract]
Sales	$ 940,203	$ 747,718	$ 801,217
Cost of sales	450,629	380,028	388,231
Gross profit	489,574	367,690	412,986
Operating expenses:
Selling, general and administrative	389,824	352,503	335,681
Research and development	198,877	169,667	139,114
Acquired in-process research and development expenses	0	78,750	31,039
Total operating expenses	588,701	600,920	505,834
Operating loss	(99,127)	(233,230)	(92,848)
Other income (expense), net:
Interest income and other, net	17,993	22,858	6,057
Interest expense	(7,415)	(9,882)	(6,208)
Loss from equity method investments	(2,053)	0	0
Loss on extinguishment of debt	(1,268)	0	0
Change in fair value of common stock warrants	0	0	147
Total other income (expense), net	7,257	12,976	(4)
Loss before income taxes	(91,870)	(220,254)	(92,852)
Income tax expense	4,155	2,357	1,742
Net loss	(96,025)	(222,611)	(94,594)
Other comprehensive income (loss):
Unrealized gain (loss) on short-term investments	(311)	3,606	(2,233)
Foreign currency translation gains (losses)	(3,005)	(420)	1,032
Comprehensive loss	$ (99,341)	$ (219,425)	$ (95,795)
Net loss per share - basic (in dollars per share)	$ (1.47)	$ (3.43)	$ (1.47)
Net loss per share - diluted (in dollars per share)	$ (1.47)	$ (3.43)	$ (1.47)
Weighted average shares used to compute basic net loss per share (in shares)	65,451,000	64,969,000	64,146,000
Weighted average shares used to compute diluted net loss per share (in shares)	65,451,000	64,969,000	64,146,000

Stockholders' Equity

12 Months Ended

Dec. 31, 2024

Equity [Abstract]

Stockholders' Equity

Stockholders’ Equity

Shares Reserved for Future Issuance

The following shares of the Company's common stock were reserved for future issuance at December 31, 2024 (in thousands):


Shares reserved for issuance upon conversion of Convertible Senior Notes			8,202
Shares underlying outstanding warrants			194
Shares underlying outstanding stock options			3,527
Shares underlying unvested restricted stock units			3,739
Shares authorized for issuance pursuant to awards granted under the ESPP			2,684
Shares authorized for future equity award grants			1,862
Total			20,208

Common Stock Warrants

Warrants outstanding to purchase shares of the Company's common stock as of December 31, 2024 were as follows:

Issue Date

Exercise Price Per Share

Warrants Outstanding

Expiration Date of Warrants Outstanding

March 2017

$23.50

193,788

March 2027

Each warrant allows the holder to purchase one share of common stock at the per share exercise price of the warrant.

Stock Incentive Plans

In May 2023, the Company’s stockholders approved the 2023 Long-Term Incentive Plan (2023 Plan), under which 2,602,184 shares of common stock were initially reserved for issuance. Under the 2023 Plan, the Company may grant stock options, stock appreciation rights, restricted stock and restricted stock units to individuals who are employees, officers, directors or consultants of the Company at the time of grant. The 2023 Plan replaced the Company’s Amended and Restated 2013 Stock Incentive Plan (2013 Plan), and no further equity awards will be granted under the 2013 Plan. In May 2024, the Company’s stockholders approved the 2023 Long-Term Incentive Plan, as amended, to increase the number of shares authorized for issuance under the plan by 3,000,000 shares.

Stock Options

The maximum term of stock options granted under the Company’s active plans is ten years. Stock options have an exercise price equal to the closing price of the Company's common stock on the applicable award date. Stock options granted before 2022 generally vested over a four-year period as to 25% of the underlying shares on the first anniversary of the grant date, with the balance of the options vesting monthly over the following three years. Stock options granted in 2022 and thereafter vest over a three-year period as to 33% of the underlying shares on the first anniversary of the grant date, with the balance of the options vesting monthly over the following two years.

The following table summarizes stock option activities under the Company’s stock incentive plans:


	Total Stock Options	Weighted- Average Exercise Price Per Share		Weighted- Average Remaining Contractual Life (in years)	Aggregate Intrinsic Value (in thousands)
Outstanding at December 31, 2021	4,814,846	$	57.08	7.07	$	452,081
Granted	83,008	$	65.28
Exercised	(280,275)	$	32.58		$	13,473
Canceled/forfeited/expired	(175,266)	$	77.93		$	2,143
Outstanding at December 31, 2022	4,442,313	$	57.95	6.12	$	30,236
Granted	—	$	—
Exercised	(72,536)	$	17.86		$	1,400
Canceled/forfeited/expired	(473,773)	$	90.14		$	95
Outstanding at December 31, 2023	3,896,004	$	54.79	5.30	$	11,703
Granted	—	$	—
Exercised	(112,171)	$	19.90		$	2,483
Canceled/forfeited/expired	(257,277)	$	85.51		$	—
Outstanding at December 31, 2024	3,526,556	$	53.65	4.32	$	16,147
Vested and expected to vest at December 31, 2024	3,525,815	$	53.65	4.32	$	16,147
Exercisable at December 31, 2024	3,496,909	$	53.44	4.30	$	16,147

Restricted Stock Units

Restricted stock units (RSUs) have a grant value equal to the closing price of the Company’s common stock on the award date. RSUs granted before March 2022 generally vest over a four-year period based on continuous service as to 25% of the underlying shares on the first anniversary of the award, with the balance of the RSUs vesting quarterly over the following three years. RSUs granted in March 2022 and thereafter generally vest over a three-year period based on continuous service to the Company as to 33% of the underlying shares on the first anniversary of the award, with the balance of the RSUs vesting quarterly over the following two years. In addition, the Company granted 151,660, 110,074 and 53,662 performance-based RSUs during the years ended December 31, 2024, 2023 and 2022, respectively, of which 151,660, 92,308 and 48,139 units remained outstanding at December 31, 2024. The Company estimated the fair value of performance-based RSUs at the date of grant using the closing price of the Company’s common stock on the date of grant, and the probability that the specified performance metrics of the performance-based RSU would be met. These awards vest upon the Company’s actual performance relative to predefined performance metrics and subject to the awardee’s continuous service through the respective measurement dates as defined in the award agreements. For certain performance-based RSUs with market-based criteria, the Company used a Monte Carlo methodology to estimate the fair value at the date of grant.

The following table summarizes RSU activities, which includes performance-based RSUs, for the Company’s stock incentive plans:


	Total RSUs	Weighted-Average Grant Date Fair Value		Aggregate Intrinsic Value (in thousands)
Unvested awards outstanding at December 31, 2021	610,731	$	95.08	$	91,927
Granted	1,542,859	$	67.09
Vested	(202,215)	$	91.99
Canceled/forfeited	(117,543)	$	84.20
Unvested awards outstanding at December 31, 2022	1,833,832	$	72.57	$	82,431
Granted	2,359,907	$	28.13
Vested	(735,155)	$	73.17
Canceled/forfeited	(282,425)	$	59.17
Unvested awards outstanding at December 31, 2023	3,176,159	$	40.61	$	93,951
Granted	2,332,553	$	44.52
Vested	(1,475,409)	$	42.76
Canceled/forfeited	(294,533)	$	41.05
Unvested awards outstanding at December 31, 2024	3,738,770	$	42.17	$	134,670
Awards expected to vest at December 31, 2024	3,571,843	$	42.35	$	128,658

The aggregate fair value of RSUs that vested during the years ended December 31, 2024, 2023 and 2022 was $58.5 million, $21.2 million, and $12.7 million, respectively, which represents the market value of the Company’s common stock on the date the RSUs vested. The number of RSUs vested includes shares of common stock the Company withheld on behalf of employees to satisfy the minimum statutory tax withholding requirements. RSUs that are expected to vest are net of estimated future forfeitures.

Employee Stock Purchase Plan

The Company’s Employee Stock Purchase Plan (ESPP) was approved by the Board in October 2013. The ESPP enables eligible employees to purchase shares of the Company’s common stock using their after-tax payroll deductions, subject to certain conditions. The ESPP is intended to qualify as an “employee stock purchase plan” within the meaning of Section 423 of the Code. Eligible employees may contribute, through payroll deductions, up to 15% of their earnings for the purchase of common stock under the ESPP. The purchase price of common stock under the ESPP is the lesser of: (a) 85% of the fair market value of a share of the Company’s common stock on the first date of an offering or (b) 85% of the fair market value of a share of the Company’s common stock on the date of purchase. Generally, offerings under the ESPP consist of a two-year offering period with four six-month purchase periods which begin in May and November of each year.

During the years ended December 31, 2024, 2023 and 2022, 770,362, 499,431 and 262,936 shares of our common stock, respectively, were purchased under the ESPP for proceeds of $12.2 million, $10.7 million and $12.7 million, respectively.

Stock-Based Compensation

The following table summarizes the allocation of stock-based compensation expense included in the consolidated statements of operations for all stock-based compensation arrangements (in thousands):


	Year Ended December 31,
		2024		2023		2022
Cost of sales		$	7,361	$	6,212	$	7,685
Selling, general and administrative		62,794		56,303		57,196
Research and development		31,228		25,561		20,037
Total stock-based compensation expense		$	101,383	$	88,076	$	84,918

The total stock-based compensation expense capitalized as part of the cost of the Company’s inventories was $1.8 million at December 31, 2024, and $2.0 million at December 31, 2023.

At December 31, 2024, the total unamortized stock-based compensation expense of approximately $121.0 million will be recognized over the remaining weighted average vesting term of approximately 1.9 years.

The Company estimates the fair value of stock options using the Black-Scholes option pricing model on the grant date. No stock options were granted in 2024 or 2023. For the year ended December 31, 2022, the Company’s assumptions used in the Black-Scholes model were as follows: weighted average grant date fair value of $42.16 per share, risk-free interest rate of 2.7%, dividend yield of 0.0%, expected volatility of 72.0%, and expected term of 5.8 years.

The Company records stock-based compensation expense associated with the ESPP using the Black-Scholes option pricing model. Valuations are performed on the grant date at the beginning of the purchase period, which generally occurs in May and November of each year. The assumptions used in the Black-Scholes option pricing model for the ESPP were as follows:


					ESPP
	Year Ended December 31,
		2024			2023			2022
Weighted average grant date fair value (per share)		$	17.01		$	10.35		$	21.89
Risk-free interest rate		4.7		%	4.9		%	3.4		%
Dividend yield		0.0		%	0.0		%	0.0		%
Expected volatility		67.5		%	63.9		%	56.9		%
Expected term (in years)		1.3			1.3			1.3

Risk-free Interest Rate. The risk-free interest rate assumption was based on the United States Treasury’s rates for United States Treasury zero-coupon bonds with maturities similar to those of the expected term of the award being valued.

Expected Dividend Yield. The dividend yield is zero because the Company has never declared or paid any cash dividends and does not presently plan to pay cash dividends in the foreseeable future.

Expected Volatility. The expected volatility was estimated based on a weighted-average of the Company’s actual historical volatility of its common stock measured over the expected term.

Expected Term. The Company utilized the simplified method for estimating the expected term of stock option grants. Under this approach, the weighted-average expected term is presumed to be the average of the vesting term and the contractual term of the option. The Company estimates the expected term of the ESPP using expected life for each tranche during the two-year offering period.

The Company also estimates forfeitures at the time of grant, and revises those estimates in subsequent periods if actual forfeitures differ from its estimates. Historical data was used to estimate pre-vesting option forfeitures and record stock-based compensation expense only for those awards that are expected to vest.

- Definition

The entire disclosure for equity.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481112/505-10-50-13

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Subparagraph (h)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481112/505-10-50-13

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 14
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481112/505-10-50-14

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
-SubTopic 235
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477968/946-235-50-2

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
-SubTopic 235
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477968/946-235-50-2

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
-SubTopic 505
-Name Accounting Standards Codification
-Section 50
-Paragraph 6
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478448/946-505-50-6

Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Topic 815
-SubTopic 40
-Name Accounting Standards Codification
-Section 50
-Paragraph 6
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480237/815-40-50-6

Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.3-04)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480008/505-10-S99-1

Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Topic 235
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08(e)(1))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480678/235-10-S99-1

Reference 10: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 505
-Name Accounting Standards Codification
-Publisher FASB
-URI https://asc.fasb.org/505/tableOfContent

Reference 11: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481112/505-10-50-13

Reference 12: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Subparagraph (g)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481112/505-10-50-13

Reference 13: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Subparagraph (i)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481112/505-10-50-13

Reference 14: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 14
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481112/505-10-50-14

Reference 15: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 14
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481112/505-10-50-14

Reference 16: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 16
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481112/505-10-50-16

Reference 17: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 18
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481112/505-10-50-18

Reference 18: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 18
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481112/505-10-50-18

Reference 19: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 18
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481112/505-10-50-18

+ Details

Leases - Future Minimum Payments Under Non-cancellable Operating Leases (Details) - USD ($) $ in Thousands	Dec. 31, 2024	Dec. 31, 2023
Leases [Abstract]
2025	$ 18,208
2026	18,102
2027	18,406
2028	14,890
2029	13,413
Thereafter	76,891
Total undiscounted lease payments	159,910
Less: amount representing interest	(35,281)
Present value of operating lease liabilities	124,629
Less: current portion of operating lease liabilities	(18,208)	$ (17,060)
Operating lease liabilities - long-term	$ 106,421	$ 113,572

Debt - Interest Expense Recognized (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Debt Instrument [Line Items]
Amortization of debt issuance costs	$ 2,089	$ 2,204	$ 1,896
Convertible Senior Notes \| Convertible Senior Notes
Debt Instrument [Line Items]
Contractual interest expense	5,161	7,565	4,313
Amortization of debt issuance costs	1,906	1,803	1,896
Total interest expense	$ 7,067	9,368	$ 6,209
Additional interest		$ 3,300

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

+ Details

Summary of Significant Accounting Policies - Anti-Dilutive Securities (Details) - shares shares in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per share, amount (in shares)	11,436	4,986	5,012
Options to purchase common stock
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per share, amount (in shares)	124	135	1,138
Unvested restricted stock units
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per share, amount (in shares)	2,858	2,089	1,118
Warrants to purchase common stock
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per share, amount (in shares)	194	194	194
Awards granted under the ESPP
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per share, amount (in shares)	58	14	8
Convertible senior notes (if-converted)
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per share, amount (in shares)	8,202	2,554	2,554

Stockholders' Equity - Common Stock Warrants (Details) - Common Stock Warrant Expiring March 2027	Dec. 31, 2024 $ / shares shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Warrants exercise price (in dollars per share) \| $ / shares	$ 23.50
Warrants outstanding (in shares) \| shares	193,788

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

+ Details

Short-Term Investments - Estimated Fair Value of Short-Term Investments (Details) - USD ($) $ in Thousands	Dec. 31, 2024	Dec. 31, 2023
Cash Cash Equivalents And Short Term Investments [Line Items]
Amortized Cost	$ 368,657	$ 408,295
Gross Unrealized Gain	759	1,025
Gross Unrealized Loss	(321)	(276)
Estimated Fair Value	369,095	409,044
United States Government-sponsored enterprises
Cash Cash Equivalents And Short Term Investments [Line Items]
Amortized Cost	133,139	181,851
Gross Unrealized Gain	275	518
Gross Unrealized Loss	(134)	(215)
Estimated Fair Value	133,280	182,154
United States Treasury securities
Cash Cash Equivalents And Short Term Investments [Line Items]
Amortized Cost	103,645	114,714
Gross Unrealized Gain	197	318
Gross Unrealized Loss	(140)	(28)
Estimated Fair Value	103,702	115,004
Commercial paper
Cash Cash Equivalents And Short Term Investments [Line Items]
Amortized Cost	23,225	72,505
Gross Unrealized Gain	39	33
Gross Unrealized Loss	0	(27)
Estimated Fair Value	23,264	72,511
Corporate debt securities
Cash Cash Equivalents And Short Term Investments [Line Items]
Amortized Cost	105,635	39,225
Gross Unrealized Gain	248	156
Gross Unrealized Loss	(47)	(6)
Estimated Fair Value	105,836	$ 39,375
Foreign government bonds
Cash Cash Equivalents And Short Term Investments [Line Items]
Amortized Cost	3,013
Gross Unrealized Gain	0
Gross Unrealized Loss	0
Estimated Fair Value	$ 3,013

Cover Page - USD ($) $ in Billions	12 Months Ended
Cover Page - USD ($) $ in Billions	Dec. 31, 2024	Feb. 21, 2025	Jun. 30, 2024
Cover [Abstract]
Document Type	10-K
Document Annual Report	true
Document Period End Date	Dec. 31, 2024
Current Fiscal Year End Date	--12-31
Document Transition Report	false
Entity File Number	001-36189
Entity Registrant Name	Tandem Diabetes Care, Inc.
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	20-4327508
Entity Address, Address Line One	12400 High Bluff Drive
Entity Address, City or Town	San Diego
Entity Address, State or Province	CA
Entity Address, Postal Zip Code	92130
City Area Code	858
Local Phone Number	366-6900
Title of 12(b) Security	Common Stock, par value $0.001 per share
Trading Symbol	TNDM
Security Exchange Name	NASDAQ
Entity Well-known Seasoned Issuer	Yes
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Large Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
ICFR Auditor Attestation Flag	true
Document Financial Statement Error Correction [Flag]	false
Entity Shell Company	false
Entity Public Float			$ 2.6
Entity Common Stock, Shares Outstanding (in shares)		66,473,272
Documents Incorporated by Reference	Portions of the registrant’s definitive Proxy Statement on Schedule 14A for the 2025 Annual Meeting of Stockholders to be filed with the Securities and Exchange Commission not later than 120 days after the end of the fiscal year covered by this Form 10-K, are incorporated by reference in Part III, Items 10-14 of this Form 10-K.
Amendment Flag	false
Document Fiscal Year Focus	2024
Document Fiscal Period Focus	FY
Entity Central Index Key	0001438133

Pay vs Performance Disclosure - USD ($) $ in Thousands	3 Months Ended		12 Months Ended
Pay vs Performance Disclosure - USD ($) $ in Thousands	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Pay vs Performance Disclosure
Net loss	$ 755	$ (30,002)	$ (96,025)	$ (222,611)	$ (94,594)

- Definition

The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 250
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 6
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147483443/250-10-50-6

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 250
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 9
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147483443/250-10-50-9

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 805
-SubTopic 60
-Name Accounting Standards Codification
-Section 65
-Paragraph 1
-Subparagraph (g)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147476176/805-60-65-1

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-SubTopic 323
-Name Accounting Standards Codification
-Section 65
-Paragraph 2
-Subparagraph (g)(3)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478666/740-323-65-2

Reference 5: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 220
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03(20))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147483621/220-10-S99-2

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Topic 235
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08(g)(1)(ii))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480678/235-10-S99-1

Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Topic 323
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481687/323-10-50-3

Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Topic 825
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 28
-Subparagraph (f)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482907/825-10-50-28

Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Topic 220
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 6
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482765/220-10-50-6

Reference 10: http://www.xbrl.org/2003/role/disclosureRef
-Topic 250
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147483443/250-10-50-3

Reference 11: http://www.xbrl.org/2003/role/disclosureRef
-Topic 250
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (b)(2)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147483443/250-10-50-1

Reference 12: http://www.xbrl.org/2003/role/disclosureRef
-Topic 815
-SubTopic 40
-Name Accounting Standards Codification
-Section 65
-Paragraph 1
-Subparagraph (f)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480175/815-40-65-1

Reference 13: http://www.xbrl.org/2003/role/disclosureRef
-Topic 250
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 8
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147483443/250-10-50-8

Reference 14: http://www.xbrl.org/2003/role/disclosureRef
-Topic 250
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 11
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147483443/250-10-50-11

Reference 15: http://www.xbrl.org/2003/role/disclosureRef
-Topic 250
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 11
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147483443/250-10-50-11

Reference 16: http://www.xbrl.org/2003/role/disclosureRef
-Topic 250
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 4
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147483443/250-10-50-4

Reference 17: http://www.xbrl.org/2003/role/exampleRef
-Topic 946
-SubTopic 830
-Name Accounting Standards Codification
-Section 55
-Paragraph 10
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479168/946-830-55-10

Reference 18: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
-SubTopic 220
-Name Accounting Standards Codification
-Section 45
-Paragraph 7
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479105/946-220-45-7

Reference 19: http://www.xbrl.org/2003/role/disclosureRef
-Topic 944
-SubTopic 220
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-04(18))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477250/944-220-S99-1

Reference 20: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
-SubTopic 220
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.6-07(9))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479134/946-220-S99-1

Reference 21: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
-SubTopic 220
-Name Accounting Standards Codification
-Section S99
-Paragraph 3
-Subparagraph (SX 210.6-09(1)(d))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479134/946-220-S99-3

Reference 22: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1A
-Subparagraph (SX 210.13-01(a)(4)(i))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480097/470-10-S99-1A

Reference 23: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 470
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1A
-Subparagraph (SX 210.13-01(a)(4)(ii))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480097/470-10-S99-1A

Reference 24: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1A
-Subparagraph (SX 210.13-01(a)(4)(iii)(A))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480097/470-10-S99-1A

Reference 25: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1A
-Subparagraph (SX 210.13-01(a)(4)(iv))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480097/470-10-S99-1A

Reference 26: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1A
-Subparagraph (SX 210.13-01(a)(5))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480097/470-10-S99-1A

Reference 27: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1B
-Subparagraph (SX 210.13-02(a)(4)(i))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480097/470-10-S99-1B

Reference 28: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1B
-Subparagraph (SX 210.13-02(a)(4)(iii)(A))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480097/470-10-S99-1B

Reference 29: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1B
-Subparagraph (SX 210.13-02(a)(4)(iii)(B))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480097/470-10-S99-1B

Reference 30: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1B
-Subparagraph (SX 210.13-02(a)(4)(iv))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480097/470-10-S99-1B

Reference 31: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1B
-Subparagraph (SX 210.13-02(a)(5))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480097/470-10-S99-1B

Reference 32: http://www.xbrl.org/2003/role/disclosureRef
-Topic 260
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 60B
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482689/260-10-45-60B

Reference 33: http://www.xbrl.org/2003/role/disclosureRef
-Topic 205
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 7
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147483499/205-20-50-7

Reference 34: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 230
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 28
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482740/230-10-45-28

Reference 35: http://www.xbrl.org/2003/role/disclosureRef
-Topic 220
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 1A
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482790/220-10-45-1A

Reference 36: http://www.xbrl.org/2003/role/disclosureRef
-Topic 220
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 1B
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482790/220-10-45-1B

Reference 37: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 942
-SubTopic 220
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-04(22))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478524/942-220-S99-1

+ Details

Summary of Significant Accounting Policies - Additional Information (Details) - USD ($)	1 Months Ended	8 Months Ended	12 Months Ended
	Nov. 30, 2024	Jun. 30, 2024	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Summary Of Significant Accounting Policies [Line Items]
Operating lease impairment charge			$ 0	$ 0	$ 0
Investment owned at cost			0	10,100,000
Impairment charges			2,000,000	0	0
Equity method investments			74,545,000	0
Loss from equity method investments			(2,053,000)	$ 0	$ 0
Guarantor obligations, revenue recognized			$ 30,200,000
Convertible Senior Notes
Summary Of Significant Accounting Policies [Line Items]
Payments to acquire investments		$ 22,200,000
Minimum
Summary Of Significant Accounting Policies [Line Items]
Estimated useful lives of the assets			3 years
Maximum
Summary Of Significant Accounting Policies [Line Items]
Estimated useful lives of the assets			7 years
Private Company Investees
Summary Of Significant Accounting Policies [Line Items]
Invest an additional amount	$ 46,400,000
Outstanding equity percentage (more than)	20.00%
Insulin Pump
Summary Of Significant Accounting Policies [Line Items]
Warranty period offered			4 years
Slim cartridges and infusion sets
Summary Of Significant Accounting Policies [Line Items]
Warranty period offered			6 months

Leases - Operating Leases Weighted-Average Remaining Lease Term and Discount Rate (Details)	Dec. 31, 2024	Dec. 31, 2023
Leases [Abstract]
Weighted-average remaining lease term (in years)	9 years 2 months 12 days	10 years 2 months 12 days
Weighted-average discount rate used to determine operating lease liabilities	5.30%	5.40%

Composition of Certain Financial Statement Items - Summary of Property and Equipment (Details) - USD ($) $ in Thousands	Dec. 31, 2024	Dec. 31, 2023
Property, Plant and Equipment [Line Items]
Total cost	$ 140,978	$ 129,336
Less: accumulated depreciation and amortization	(62,828)	(52,794)
Total property and equipment, net	78,150	76,542
Leasehold improvements
Property, Plant and Equipment [Line Items]
Total cost	37,106	37,565
Office furniture and equipment
Property, Plant and Equipment [Line Items]
Total cost	11,813	11,842
Computer equipment and software
Property, Plant and Equipment [Line Items]
Total cost	9,811	10,340
Manufacturing and scientific equipment
Property, Plant and Equipment [Line Items]
Total cost	$ 82,248	$ 69,589

Short-Term Investments (Tables)

12 Months Ended

Dec. 31, 2024

Investments, Debt and Equity Securities [Abstract]

Schedule of Estimated Fair Value of Short-Term Investments

The following represents a summary of the estimated fair value of short-term investments at December 31, 2024 and December 31, 2023 (in thousands):


At December 31, 2024	Amortized Cost		Gross Unrealized Gain		Gross Unrealized Loss		Estimated Fair Value
Available-for-sale securities:
United States Government-sponsored enterprises	$	133,139	$	275	$	(134)	$	133,280
United States Treasury securities	103,645		197		(140)		103,702
Commercial paper	23,225		39		—		23,264
Corporate debt securities	105,635		248		(47)		105,836
Foreign government bonds	3,013		—		—		3,013

Total	$	368,657	$	759	$	(321)	$	369,095


At December 31, 2023	Amortized Cost		Gross Unrealized Gain		Gross Unrealized Loss		Estimated Fair Value
Available-for-sale securities:
United States Government-sponsored enterprises	$	181,851	$	518	$	(215)	$	182,154
United States Treasury securities	114,714		318		(28)		115,004
Commercial paper	72,505		33		(27)		72,511
Corporate debt securities	39,225		156		(6)		39,375

Total	$	408,295	$	1,025	$	(276)	$	409,044

Schedule of Contractual Maturities of Available -For-Sale Debt Securities

The contractual maturities of available-for-sale debt securities as of December 31, 2024, were as follows (in thousands):


	Years to Maturity
At December 31, 2024	Within One Year		One to Two Years		Two to Three Years		Estimated Fair Value
United States Government-sponsored enterprises	$	44,717	$	39,193	$	49,370	$	133,280
United States Treasury securities	85,400		17,307		995		103,702
Commercial paper	23,264		—		—		23,264
Corporate debt securities	60,514		45,322		—		105,836
Foreign government bonds	—		—		3,013		3,013

Total	$	213,895	$	101,822	$	53,378	$	369,095

Income Taxes (Tables)

12 Months Ended

Dec. 31, 2024

Income Tax Disclosure [Abstract]

Schedule of Income (Loss) Before Provision for Income Taxes

The income (loss) before provision for income taxes for the Company’s operations was as follows (in thousands):


	Year Ended December 31,
	2024		2023		2022
United States	$	(78,156)	$	(135,411)	$	(94,033)
Foreign	(13,714)		(84,843)		1,181
Income (loss) before provision for income taxes	$	(91,870)	$	(220,254)	$	(92,852)

Schedule of Components of Income Tax Expense

The components of income tax expense were as follows (in thousands):


	Year Ended December 31,
	2024		2023		2022
Current:
Federal	$	636	$	308	$	216
State	1,143		345		1,228
Foreign	2,376		1,704		298
Total current tax expense	4,155		2,357		1,742
Deferred:
Federal	—		—		—
State	—		—		—
Foreign	—		—		—
Total deferred income tax benefit	—		—		—
Income tax expense	$	4,155	$	2,357	$	1,742

Schedule of Effective Income Tax Rate Reconciliation

The expense for income taxes reconciles to the amount computed by applying the federal statutory rate to loss before taxes as follows (in thousands):


	Year Ended December 31,
	2024		2023		2022
Income tax expense (benefit) at federal statutory rate (1)	$	(19,293)	$	(46,253)	$	(19,499)
State income tax, net of federal benefit	(1,444)		(1,313)		(926)
Convertible debt leg-out	1,658		—		—
Warrants revaluation	—		—		(31)
Research and development credits	(7,865)		(6,283)		(6,263)
Section 382 limitation	—		(5)		—
Stock-based compensation	5,772		14,904		2,282
Officers' compensation	1,043		1,547		2,931
Recognition of acquired deferred tax assets	—		(5,048)		—
Acquired IPR&D expenses	—		14,938		6,518
Cross-border tax impacts	(1,422)		(307)		31
Foreign rate differential	2,075		7		37
Other	1,159		1,374		894
Change in valuation allowance	22,472		28,796		15,768
Income tax expense	$	4,155	$	2,357	$	1,742

(1)For the years ended December 31, 2024, 2023 and 2022, the federal statutory tax rate was 21%.

Schedule of Deferred Tax Assets and Liabilities


	December 31,
	2024		2023
Deferred tax assets:
Net operating loss (NOL) carryforwards	$	40,536	$	54,802
Research and development tax credits carryforwards	32,298		27,516
Capitalized research and development expenses	74,974		52,875
Accrued compensation	38,053		32,097
Lease liabilities	29,165		31,037
Warranty reserve	12,222		8,786
Other	8,610		11,992
Total deferred tax assets	235,858		219,105
Deferred tax liabilities:
Operating lease right-of-use assets	(19,792)		(20,869)
Fixed assets	(5,485)		(6,916)
Other	(218)		(656)
Total deferred tax liabilities	(25,495)		(28,441)
Less valuation allowance	(210,363)		(190,664)
Net deferred tax assets	$	—	$	—

Schedule of Unrecognized Tax Benefits

The following table summarizes the activity related to the Company’s gross unrecognized tax benefits at the beginning and end of the years ended December 31, 2024, 2023 and 2022 (in thousands):


	Year Ended December 31,
	2024		2023		2022
Gross unrecognized tax benefits at the beginning of the year	$	21,527	$	16,986	$	13,589
Increases related to current year positions	5,947		3,961		3,403
Increases (decreases) related to prior year positions	—		580		(6)
Gross unrecognized tax benefits at the end of the year	$	27,474	$	21,527	$	16,986

CONSOLIDATED STATEMENTS OF CASH FLOWS (Parenthetical) $ in Thousands	Dec. 31, 2024 USD ($)
Statement of Cash Flows [Abstract]
Unamortized debt issuance costs	$ 9,400
Repurchased face amount	$ 246,740

Fourth Quarter Financial Data (Unaudited) - Financial Information of Normal Recurring Adjustments (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Sales	$ 282,648	$ 196,796	$ 940,203	$ 747,718	$ 801,217
Gross profit	157,455	93,295	489,574	367,690	412,986
Operating expenses	158,036	128,355	588,701	600,920	505,834
Operating loss	(581)	(35,060)	(99,127)	(233,230)	(92,848)
Net income (loss)	$ 755	$ (30,002)	$ (96,025)	$ (222,611)	$ (94,594)
Net income (loss) per share, basic (in dollars per share)	$ 0.01	$ (0.46)	$ (1.47)	$ (3.43)	$ (1.47)
Weighted average shares used to compute basic net loss per share (in shares)	65,939,000	65,369,000	65,451,000	64,969,000	64,146,000
Net income (loss) per share, diluted (in dollars per share)	$ 0.01	$ (0.46)	$ (1.47)	$ (3.43)	$ (1.47)
Weighted average shares used to compute diluted net loss per share (in shares)	66,157,000	65,369,000	65,451,000	64,969,000	64,146,000
Guarantor obligations, revenue recognized			$ 30,200
Net revenue recognized (deferred) for Tandem Choice program
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Guarantor obligations, revenue recognized	$ 30,200
Deferred revenue		$ 25,100		$ 25,100
Cost of sales	$ 600

Debt (Tables)

12 Months Ended

Dec. 31, 2024

Debt Disclosure [Abstract]

Schedule of Convertible Senior Notes

The Company estimated the fair value of its convertible senior notes based on Level 2 quoted market prices as follows (in thousands):


	Fair Value Measurements at
	December 31, 2024		December 31, 2023
Convertible Senior Notes due 2025	$	39,130	$	271,688
Convertible Senior Notes due 2029	407,752		*
Total fair value of outstanding convertible senior notes	$	446,882	$	271,688

* Not applicable as no notes were outstanding at this date.

The net carrying amount of the Company’s convertible senior notes on the consolidated balance sheets consisted of the following (in thousands):


	December 31, 2024		December 31, 2023
Principal amount:
Convertible Senior Notes Due 2025	$	40,760	$	287,500
Convertible Senior Notes Due 2029	316,250		*
Total principal amount	357,010		287,500
Unamortized debt issuance costs	(8,074)		(2,465)
Total debt, net	$	348,936	$	285,035
Less: current portion	(40,670)		—
Long-term senior convertible notes	$	308,266	$	285,035

* Not applicable as no notes were outstanding at this date.

The following table summarizes the effective interest rates for each of our convertible senior notes for the periods shown:


	Year Ended December 31,
		2024		2023		2022
Effective interest rate:
Convertible Senior Notes Due 2025		2.1	%	2.2	%	2.2	%
Convertible Senior Notes Due 2029		2.1	%	*		*

* Not applicable as no notes were outstanding at this date.

Schedule of Interest Expense Recognized

The following table details interest expense related to the Notes recognized for the years ended December 31, 2024, and 2023 (in thousands):


	Year Ended December 31,
		2024		2023		2022
Contractual interest expense(1)		$	5,161	$	7,565	$	4,313
Amortization of debt issuance costs		1,906		1,803		1,896

Total interest expense		$	7,067	$	9,368	$	6,209

(1) Contractual interest expense for the year ended December 31, 2023 included $3.3 million of additional interest as discussed above.

Employee Benefits	12 Months Ended
Employee Benefits	Dec. 31, 2024
Retirement Benefits [Abstract]
Employee Benefits	Employee Benefits Defined Contribution Plans The Company has defined contribution plans for its employees. The Company’s largest defined contribution plan is the 401(k) plan for employees in the United States who are at least 18 years of age. Employees are eligible to participate in the plan beginning on the first day of the calendar month following their date of hire. Unless they affirmatively elect otherwise, employees are automatically enrolled in the plan following 30 days from date of hire or entry date. Under the terms of the plan, employees may make voluntary contributions as a percent of compensation and the Company may elect to match a discretionary percentage of employee contributions. The total cost recognized by the Company for the 401(k) plan was $4.6 million, $4.2 million and $4.2 million, respectively, for the years ended December 31, 2024, 2023 and 2022. The Company’s contributions for its defined contribution plans for employees outside the United States were not material for each of the years ended December 31, 2024, 2023 and 2022

Income Taxes

12 Months Ended

Dec. 31, 2024

Income Tax Disclosure [Abstract]

Income Taxes

The income (loss) before provision for income taxes for the Company’s operations was as follows (in thousands):


	Year Ended December 31,
	2024		2023		2022
United States	$	(78,156)	$	(135,411)	$	(94,033)
Foreign	(13,714)		(84,843)		1,181
Income (loss) before provision for income taxes	$	(91,870)	$	(220,254)	$	(92,852)

The components of income tax expense were as follows (in thousands):


	Year Ended December 31,
	2024		2023		2022
Current:
Federal	$	636	$	308	$	216
State	1,143		345		1,228
Foreign	2,376		1,704		298
Total current tax expense	4,155		2,357		1,742
Deferred:
Federal	—		—		—
State	—		—		—
Foreign	—		—		—
Total deferred income tax benefit	—		—		—
Income tax expense	$	4,155	$	2,357	$	1,742

The expense for income taxes reconciles to the amount computed by applying the federal statutory rate to loss before taxes as follows (in thousands):


	Year Ended December 31,
	2024		2023		2022
Income tax expense (benefit) at federal statutory rate (1)	$	(19,293)	$	(46,253)	$	(19,499)
State income tax, net of federal benefit	(1,444)		(1,313)		(926)
Convertible debt leg-out	1,658		—		—
Warrants revaluation	—		—		(31)
Research and development credits	(7,865)		(6,283)		(6,263)
Section 382 limitation	—		(5)		—
Stock-based compensation	5,772		14,904		2,282
Officers' compensation	1,043		1,547		2,931
Recognition of acquired deferred tax assets	—		(5,048)		—
Acquired IPR&D expenses	—		14,938		6,518
Cross-border tax impacts	(1,422)		(307)		31
Foreign rate differential	2,075		7		37
Other	1,159		1,374		894
Change in valuation allowance	22,472		28,796		15,768
Income tax expense	$	4,155	$	2,357	$	1,742

(1)For the years ended December 31, 2024, 2023 and 2022, the federal statutory tax rate was 21%.

Significant components of the Company’s net deferred income tax assets at December 31, 2024 and 2023 are shown in the table below (in thousands). The Company assesses all available positive and negative evidence to estimate whether sufficient future taxable income will be generated to permit use of the existing deferred tax assets. A significant piece of objective negative evidence evaluated was the cumulative book loss incurred over the three-year period ended December 31, 2024. Such objective evidence limits the ability to consider other subjective evidence, such as projections for future growth. On the basis of this analysis, a valuation allowance of $210.4 million and $190.7 million at December 31, 2024 and 2023, respectively, was recorded to offset the net deferred tax asset as realization of such asset is uncertain. However, the amount of the deferred tax asset considered realizable could be adjusted if estimates of future taxable income during the carryforward period are increased, or if objective negative evidence in the form of cumulative losses is no longer present and additional weight is given to subjective evidence such as the Company’s projections for future growth.


	December 31,
	2024		2023
Deferred tax assets:
Net operating loss (NOL) carryforwards	$	40,536	$	54,802
Research and development tax credits carryforwards	32,298		27,516
Capitalized research and development expenses	74,974		52,875
Accrued compensation	38,053		32,097
Lease liabilities	29,165		31,037
Warranty reserve	12,222		8,786
Other	8,610		11,992
Total deferred tax assets	235,858		219,105
Deferred tax liabilities:
Operating lease right-of-use assets	(19,792)		(20,869)
Fixed assets	(5,485)		(6,916)
Other	(218)		(656)
Total deferred tax liabilities	(25,495)		(28,441)
Less valuation allowance	(210,363)		(190,664)
Net deferred tax assets	$	—	$	—

As of December 31, 2024, the Company had accumulated federal and state NOL carryforwards of approximately $96.5 million, and $248.0 million, respectively. Of the total federal net operating loss carryforwards, approximately $13.2 million were generated after January 1, 2018, and therefore do not expire. NOL generated after January 1, 2018, is subject to 80% limitation in accordance with the Tax Cuts and Jobs Act of 2017. The remaining federal net operating loss carryforwards of $83.2 million will begin to expire in 2033, and state tax loss carryforwards continue to expire. The remaining California NOL carryforwards of $182.4 million will begin expiring in 2029. The Company had approximately $43.3 million of foreign tax loss carryforwards as of December 31, 2024. The foreign tax loss carryforwards begin to expire in 2025, unless previously utilized.

The Company also has federal and California research credit carryforwards of approximately $30.7 million and $29.3 million, respectively, as of December 31, 2024. The federal research credit carryforwards will begin expiring in 2040, unless previously utilized. The California research credit will carry forward indefinitely.

Utilization of the Company's net operating loss and research credit carryforwards may be subject to a substantial annual limitation due to ownership change limitations provided by Section 382 of the Internal Revenue Code of 1986, as amended, and similar state provisions. The annual limitations may result in the expiration of net operating loss carryforwards before utilization. The Company has completed analyses through December 31, 2023 to determine whether its net operating losses and credits are likely to be limited by Section 382. Based on this study, the Company determined that an ownership change, as defined under Section 382, occurred in 2018 and the resulting limitation significantly reduced the Company’s ability to utilize its net operating loss and credit carryovers before they expire. As a result, in 2019 the Company reduced its deferred tax assets for the net operating loss and research credit carryforwards that were projected to expire unused with a corresponding offset to the valuation allowance recorded against such assets. Additionally, future ownership changes under Section 382 may also limit the Company's ability to fully utilize any remaining tax benefits.

In 2022, as part of the Capillary Biomedical, Inc. transaction, the Company acquired deferred tax assets consisting of federal and state net operation loss carryovers, research tax credit carryovers, and other tax attributes of approximately $7.8 million. These deferred tax assets are subject to limitations on future use under Section 382 and some of the attributes may expire unused. The Company completed an analysis under Section 382. As a result, the Company recognized deferred tax assets, net of contra reserve, of approximately $5.0 million in 2023. The Company included these deferred tax assets in its components of deferred tax assets in the table above, to the extent that such deferred tax assets are available for future utilization, and the balances are fully offset by valuation allowance as of December 31, 2024 and 2023.

The evaluation of uncertainty in a tax position is a two-step process. The first step involves recognition. The Company determines whether it is more likely than not that a tax position will be sustained upon tax examination, including resolution of any related appeals or litigation, based on only the technical merits of the position. The technical merits of a tax position are derived from both statutory and judicial authority (legislation and statutes, legislative intent, regulations, rulings, and case law) and their applicability to the facts and circumstances of the tax position. If a tax position does not meet the more-likely-than-not recognition threshold, the benefit of that position is not recognized in the financial statements. The second step is measurement. A tax position that meets the more-likely-than-not recognition threshold is measured to determine the amount of benefit to recognize in the financial statements. The tax position is measured as the largest amount of benefit that is greater than 50% likely of being realized upon ultimate resolution with a taxing authority.

The following table summarizes the activity related to the Company’s gross unrecognized tax benefits at the beginning and end of the years ended December 31, 2024, 2023 and 2022 (in thousands):


	Year Ended December 31,
	2024		2023		2022
Gross unrecognized tax benefits at the beginning of the year	$	21,527	$	16,986	$	13,589
Increases related to current year positions	5,947		3,961		3,403
Increases (decreases) related to prior year positions	—		580		(6)
Gross unrecognized tax benefits at the end of the year	$	27,474	$	21,527	$	16,986

As of December 31, 2024 and December 31, 2023, the Company had $24.9 million and $19.2 million of unrecognized tax benefits, respectively, that, if recognized and realized would impact the effective tax rate, subject to the valuation allowance.

The Company’s practice is to recognize interest and penalties related to income tax matters in income tax expense. The Company had no accrual for interest and penalties on the Company’s consolidated balance sheets and has not recognized interest and penalties in the consolidated statements of operations for the years ended December 31, 2024, 2023 and 2022. The Company does not expect any significant increases or decreases, other than the potential reduction as a result of the Section 382 limitation, to its unrecognized tax benefits within the next 12 months.

The Company is subject to taxation in the United States and various foreign and state jurisdictions. Before 2018, the losses were all attributable to the United States. The Company’s tax years from 2006 (inception) are subject to examination by the United States and state authorities due to the carry forward of unutilized NOLs and research and development credits.

In 2021 the OECD announced an Inclusive Framework on Base Erosion and Profit Shifting including Pillar Two Model Rules defining the global minimum tax, which calls for the taxation of large multinational corporations at a minimum rate of 15%. Subsequently multiple sets of administrative guidance have been issued. Many non-US tax jurisdictions have either recently enacted legislation to adopt certain components of the Pillar Two Model Rules beginning in 2024, including the European Union Member States, with the adoption of additional components in later years or announced their plans to enact legislation in future years. We are continuing to evaluate the impacts of enacted legislation and pending legislation to enact Pillar Two Model Rules in the non-US tax jurisdictions we operate in.

Undistributed earnings of the foreign subsidiaries are indefinitely reinvested. Thus, the Company has not recognized any deferred taxes on foreign unremitted earnings.

- Definition

The entire disclosure for income tax.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 12
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482685/740-10-50-12

Reference 2: http://www.xbrl.org/2003/role/exampleRef
-Topic 740
-SubTopic 10
-Name Accounting Standards Codification
-Section 55
-Paragraph 231
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482663/740-10-55-231

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 12C
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482685/740-10-50-12C

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 12B
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482685/740-10-50-12B

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-SubTopic 270
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477891/740-270-50-1

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SAB Topic 6.I.5.Q1)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479360/740-10-S99-1

Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480990/946-20-50-13

Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Topic 235
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08(h)(2))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480678/235-10-S99-1

Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-Name Accounting Standards Codification
-Publisher FASB
-URI https://asc.fasb.org/740/tableOfContent

Reference 10: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 14
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482685/740-10-50-14

Reference 11: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 21
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482685/740-10-50-21

Reference 12: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 17
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482685/740-10-50-17

Reference 13: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 2
-Subparagraph (SAB Topic 11.C)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479360/740-10-S99-2

Reference 14: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-SubTopic 30
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482603/740-30-50-2

+ Details

Employee Benefits (Details) - USD ($) $ in Millions	12 Months Ended
Employee Benefits (Details) - USD ($) $ in Millions	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Retirement Benefits [Abstract]
Minimum age of employees for defined contribution plan	18 years
Contribution by company	$ 4.6	$ 4.2	$ 4.2

Stockholders' Equity - Restricted Stock Units (RSUs) (Details) - Restricted Stock Units (RSUs) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Total RSUs
Unvested awards outstanding at beginning balance (in shares)	3,176,159	1,833,832	610,731
RSU granted (in shares)	2,332,553	2,359,907	1,542,859
Vested (in shares)	(1,475,409)	(735,155)	(202,215)
Canceled/forfeited (in shares)	(294,533)	(282,425)	(117,543)
Unvested awards outstanding at ending balance (in shares)	3,738,770	3,176,159	1,833,832
Weighted-Average Grant Date Fair Value
Unvested awards outstanding at beginning balance (in dollars per share)	$ 40.61	$ 72.57	$ 95.08
Weighted average grant date fair value (in dollars per share)	44.52	28.13	67.09
Vested (in dollars per share)	42.76	73.17	91.99
Canceled/forfeited/expired (in dollars per share)	41.05	59.17	84.20
Unvested awards outstanding at ending balance (in dollars per share)	$ 42.17	$ 40.61	$ 72.57
Aggregate intrinsic value outstanding balance	$ 134,670	$ 93,951	$ 82,431	$ 91,927
Awards expected to vest (in shares)	3,571,843
Awards expected to vest (in dollars per share)	$ 42.35
Awards expected to vest, aggregate intrinsic value	$ 128,658

Stockholders' Equity - Assumptions Used in Black-Scholes Option-Pricing Model (Details) - Awards to be granted under the ESPP - $ / shares	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted average grant date fair value (in dollars per share)	$ 17.01	$ 10.35	$ 21.89
Risk-free interest rate	4.70%	4.90%	3.40%
Dividend yield	0.00%	0.00%	0.00%
Expected volatility	67.50%	63.90%	56.90%
Expected term (in years)	1 year 3 months 18 days	1 year 3 months 18 days	1 year 3 months 18 days

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

+ Details

Commitments and Contingencies	12 Months Ended
Commitments and Contingencies	Dec. 31, 2024
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	Commitments and Contingencies Legal and Regulatory Matters In November 2023, at the Unified Patent Court (UPC), Paris Central Division (UPC Paris), we filed a revocation action and an action for a declaration of non-infringement of EP Patent No. 2 196 231 B1 (the ’231 patent) against Roche Diabetes Care GmbH. While Roche contends that Tandem’s t:slim X2 pump infringes the ‘231 patent, we contend that our t:slim X2 pump does not infringe the ‘231 patent. Furthermore, we contend that the claims of the ‘231 patent are invalid over the prior art and should be revoked. In February 2024, Roche filed an infringement action against Tandem and its distributor in Germany at the UPC, Hamburg Local Division (UPC Hamburg) contending that Tandem’s t:slim X2 pump, and the offering, marketing, using, importing, possessing, and supplying of such devices infringes certain claims of the ‘231 patent. Roche seeks, among other things, damages and other monetary relief, costs and expenses of the legal proceedings, and an order to cease and desist the allegedly infringing activities. At the UPC Hamburg, Tandem has asserted that the t:slim X2 pump does not infringe the claims of the ‘231 patent and Tandem’s distributor has asserted that the t:slim X2 pump does not infringe the claims of the ‘231 patent and that the claims of the ‘231 patent are invalid and should be revoked. On November 6, 2024, the UPC Paris held a hearing on Tandem’s action to revoke the claims of the ‘231 patent. On December 18, 2024, the UPC Paris upheld the patent. The hearing in Hamburg on invalidity and non-infringement is scheduled for June 12, 2025. In December 2023, F. Hoffman-La Roche AG and Roche Diabetes Care GmbH (collectively, Roche), filed an infringement action at the UPC, Dusseldorf Division (UPC Dusseldorf) against Tandem Diabetes Care, Inc. and Tandem Diabetes Care Europe B.V. and Tandem’s distributors in Germany, France, the Netherlands and Denmark. Roche alleges our t:slim X2 insulin pump, and the offering, marketing, using, importing, possessing, and supplying of such devices infringe EP Patent No. 1 970 677 B1 (the ‘677 patent). While Roche contends that Tandem’s t:slim X2 pump infringes the ‘677 patent, we contend that our t:slim X2 pump does not infringe the ‘677 patent. Furthermore, we contend that the claims of the ‘677 patent are invalid over the prior art and should be revoked. Roche seeks, among other things, damages and other monetary relief, costs and expenses of the legal proceedings, and an order to cease and desist the allegedly infringing activities. On April 9, 2025, the UPC Dusseldorf will hold a hearing on Roche’s action asserting infringement of the ‘677 patent, Tandem and its distributors’ counterclaims that the t:slim X2 pump does not infringe the ‘677 patent, and Tandem and its distributors’ actions to revoke the claims of the ‘677 patent. The action seeks unspecified monetary damages and other relief. Although the Company intends to vigorously defend against these claims, there is no guarantee that the Company will prevail. Accordingly, the Company is unable to determine the ultimate outcome of this lawsuit or determine the amount or range of potential losses associated with the lawsuit. From time to time, the Company is involved in various other legal proceedings, regulatory matters, and other disputes or claims arising from or related to claims incident to the normal course of the Company’s business activities, including actions with respect to intellectual property, data privacy, employment, regulatory, product liability and contractual matters. Although the results of such legal proceedings and claims cannot be predicted with certainty, as of December 31, 2024 the Company believes it is not currently a party to any legal proceedings, regulatory matters, or other disputes or claims for which a material loss was considered probable or for which the amount or range of loss was reasonably estimable. However, regardless of the merit of the claims raised or the outcome, legal proceedings may have an adverse impact on the Company as a result of defense and settlement costs, diversion of management time and resources, and other factors. Letters of Credit As of December 31, 2024, in connection with one of the Company’s operating leases (see Note 6, “Leases”), the Company had a $4.9 million unsecured irrevocable standby letter of credit arrangement with a bank, under which the landlord of the building is the beneficiary. The Company is required to maintain the standby letter of credit throughout the term of the lease, which expires in April 2035. Purchase Obligations The Company has agreements with suppliers and other parties to purchase inventory, other goods and services and long-lived assets. Product inventory obligations consist primarily of purchase order commitments for raw materials used in the production of insulin pumps and cartridges, and finished goods infusion sets. Cancellation of outstanding purchase orders is generally allowed under the standard terms of our purchase order agreements, but may require payment of costs incurred through the date of cancellation. At December 31, 2024, obligations under our purchase agreements totaled approximately $197.1 million, of which approximately $192.7 million is scheduled to be received and become payable within one-year.

Leases

12 Months Ended

Dec. 31, 2024

Leases [Abstract]

Leases

The Company’s leases consist of operating leases for general office space, research and development, manufacturing and warehouse facilities, and equipment. These noncancellable operating leases have initial lease terms from two years to thirteen years. Certain leases include an option to renew, with renewal terms that can extend the lease term for additional periods at the Company’s sole discretion. The Company includes the renewal option period in the lease term for those leases reasonably expected to be extended at the time of lease commencement.

Headquarters Lease

In September 2021, the Company entered into a lease agreement for 181,949 square feet of general administrative, laboratory, and research and development office space (the Premises) located on High Bluff Drive in San Diego, California (Headquarters Lease). Possession of the Premises was to be tendered to the Company in two phases, with Phase I consisting of 143,850 rentable square feet, and Phase II consisting of 38,099 rentable square feet. The Headquarters Lease term expires in April 2035. The Company has two options to extend the term of the lease, with each option providing for an additional period of five years. The Headquarters Lease term was determined assuming the renewal options would not be exercised.

In December 2023, the Company entered into an agreement to sublease the Phase II portion of the leased premises under the Headquarters Lease, from January 2025 through March 2029. Future minimum payments for base rent due under Phase II of the Headquarters Lease, net of sublease rent, are estimated to be $2.2 million in total for 2025 through 2028, and $23.2 million in total for 2029 through 2035.

Operating Lease Impairment Charge

In 2023, the Company consolidated facilities by moving the administrative functions and other operations from the leased space on Vista Sorrento Parkway in San Diego, California (Vista Sorrento Lease) to the Company’s new headquarters, located on High Bluff Drive in San Diego, California. In connection with permanently ceasing use of the Vista Sorrento Lease, the Company recorded a $14.1 million impairment charge as the carrying amount of the assets related to the Vista Sorrento Lease exceeded its fair value based on the Company’s estimate of future discounted cash flows related to the leased facility. The $14.1 million charge was comprised of an $11.2 million impairment of operating lease right-of-use assets and a $2.9 million write-off of fixed assets, and was recorded as a component of selling, general and administrative expenses in the consolidated statement of operations.

Supplemental Lease Disclosure Information

The Company’s lease costs recorded in the consolidated statements of operations were as follows (in thousands):


	Year Ended December 31,
		2024		2023		2022
Operating lease cost		$	14,276	$	15,971	$	18,432
Short-term lease cost		87		108		142
Loss on lease termination and right-of-use asset impairment charges		—		11,224		5,699
Total lease cost		$	14,363	$	27,303	$	24,273

Maturities of operating lease liabilities at December 31, 2024 were as follows (in thousands):


Years Ending December 31,
2025	$	18,208
2026	18,102
2027	18,406
2028	14,890
2029	13,413
Thereafter	76,891
Total undiscounted lease payments	159,910
Less: amount representing interest	(35,281)
Present value of operating lease liabilities	124,629
Less: current portion of operating lease liabilities	(18,208)
Operating lease liabilities - long-term	$	106,421

The weighted-average remaining lease term and weighted-average discount rate for operating leases were as follows:


	December 31, 2024		December 31, 2023
Weighted-average remaining lease term (in years)	9.2		10.2
Weighted-average discount rate used to determine operating lease liabilities	5.3	%	5.4	%

Cash amounts paid included in the measurement of lease liabilities, representing operating cash flows, were as follows:


	Year Ended December 31,
	2024		2023		2022
Operating lease payments	17,941		13,864		11,960
Operating lease termination payments	—		—		4,769
Total cash payments	$	17,941	$	13,864	$	16,729

Leases For Which Accounting Has Not Yet Commenced

As of December 31, 2024, the Phase II commencement date for the Headquarters Lease had not yet occurred. Accordingly, the consolidated balance sheets at December 31, 2024 and December 31, 2023 did not include operating lease right-of-use assets and operating lease liabilities, and the consolidated statements of operations for the twelve months ended December 31, 2024, and 2023 did not include any lease costs related to Phase II of the Headquarters Lease. In addition, the above disclosures of the Company’s lease costs, maturities of operating lease liabilities, weighted-average remaining lease term, and weighted-average discount rate do not include any amounts related to Phase II of the Headquarters Lease.

Acquisitions (Details) $ in Thousands, SFr in Millions				1 Months Ended		12 Months Ended
Acquisitions (Details) $ in Thousands, SFr in Millions	Jan. 19, 2023 USD ($)	Jan. 19, 2023 CHF (SFr)	Jul. 21, 2022 USD ($)	Oct. 31, 2025 CHF (SFr)	Jan. 31, 2025 CHF (SFr)	Dec. 31, 2024 USD ($)	Dec. 31, 2023 USD ($)	Dec. 31, 2022 USD ($)	Sep. 30, 2022 CHF (SFr)
Business Acquisition [Line Items]
Equity securities without readily determinable fair value, amount									SFr 8.0
Acquired in-process research and development expenses \| $						$ 0	$ 78,750	$ 31,039
AMF Medical Acquisition
Business Acquisition [Line Items]
Payments of cash		SFr 62.4
Additional earnout payment		SFr 129.6
Milestone period	2 years	2 years
Acquired in-process research and development expenses \| $	$ 78,800
AMF Medical Acquisition \| Subsequent Event
Business Acquisition [Line Items]
Asset Acquisition, Price of Acquisition, Expected					SFr 40.0
AMF Medical Acquisition \| Subsequent Event \| Forecast
Business Acquisition [Line Items]
Asset Acquisition, Price of Acquisition, Expected				SFr 28.0
AMF Medical Acquisition \| Development Milestones
Business Acquisition [Line Items]
Additional earnout payment		SFr 38.4
AMF Medical Acquisition \| Regulatory Clearance Milestone
Business Acquisition [Line Items]
Additional earnout payment		SFr 91.2
Capillary Biomedical
Business Acquisition [Line Items]
Acquired in-process research and development expenses \| $			$ 31,000
Asset acquisition, purchase price \| $			24,700
Long term debt assumed \| $			$ 4,700			$ 4,800	$ 4,700

Composition of Certain Financial Statement Items - Additional Information (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Depreciation and amortization expense related to property and equipment	$ 14.7	$ 13.8	$ 12.3
Amortization expense related to intangible assets	1.9	$ 1.9	$ 2.0
Estimated annual amortization for 2025	$ 0.9

Income Taxes - Schedule of Unrecognized Tax Benefits (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward]
Gross unrecognized tax benefits at the beginning of the year	$ 21,527	$ 16,986	$ 13,589
Increases related to current year positions	5,947	3,961	3,403
Increases (decreases) related to prior year positions	0	580
Increases (decreases) related to prior year positions			(6)
Gross unrecognized tax benefits at the end of the year	$ 27,474	$ 21,527	$ 16,986

Fair Value Measurements - Additional Information (Details) - USD ($)	Dec. 31, 2024	Mar. 31, 2024	Mar. 08, 2024	Dec. 31, 2023	May 31, 2020
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Repurchased face amount	$ 246,740,000
Convertible Senior Notes Due 2029 \| Convertible Senior Notes
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Principal amount:	316,250,000	$ 316,300,000	$ 316,300,000
Convertible Senior Notes due 2025 \| Convertible Senior Notes
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Principal amount:	40,760,000			$ 287,500,000	$ 287,500,000
Repurchased face amount	$ 246,700,000	$ 246,700,000

Fair Value Measurements

12 Months Ended

Dec. 31, 2024

Fair Value Disclosures [Abstract]

Fair Value Measurements


	Fair Value Measurements at December 31, 2024
	Total		Level 1		Level 2		Level 3
Assets
Cash equivalents(1)	$	56,234	$	56,234	$	—	$	—
United States Government-sponsored enterprises	133,280		—		133,280		—
United States Treasury securities	103,702		103,702		—		—
Commercial paper	23,264		—		23,264		—
Corporate debt securities	105,836		—		105,836		—
Foreign government bonds	3,013		—		3,013		—

Total assets	$	425,329	$	159,936	$	265,393	$	—


	Fair Value Measurements at December 31, 2023
	Total		Level 1		Level 2		Level 3
Assets
Cash equivalents(1)	$	48,033	$	48,033	$	—	$	—
United States Government-sponsored enterprises	182,154		—		182,154		—
United States Treasury securities	115,004		115,004		—		—
Commercial paper	72,511		—		72,511		—
Corporate debt securities	39,375		—		39,375		—

Total assets	$	457,077	$	163,037	$	294,040	$	—

(1)Generally, cash equivalents include money market funds and investments with a maturity of three months or less from the date of purchase.

The Company’s Level 1 financial instruments, which are in active markets, are valued using unadjusted quoted market prices for identical instruments.

The Company’s Level 2 financial instruments are valued using market prices on less active markets with observable valuation inputs such as interest rates and yield curves. The Company obtains the fair value of Level 2 financial instruments from quoted market prices, calculated prices or quotes from third-party pricing services. The Company validates these prices through independent valuation testing and review of portfolio valuations provided by the Company’s investment managers.

There were no transfers into or out of Level 3 assets during the three months ended December 31, 2024 and 2023, respectively.

Fair Value of Financial Instruments

The carrying amounts of cash and cash equivalents, accounts receivable, accounts payable, accrued expenses, and employee-related liabilities are reasonable estimates of their fair values because of the short-term nature of these assets and liabilities. Short-term investments are carried at fair value.

In March 2024, the Company issued $316.3 million aggregate principal amount of the Company’s Convertible Senior Notes Due 2029, and repurchased $246.7 million of principal of the Company’s Convertible Senior Notes due 2025 (see Note 7, “Debt”).

The Company’s Convertible Senior Notes are carried at amortized cost on the consolidated balance sheets (see Note 7, “Debt”). The Company estimated the fair value of its convertible senior notes based on Level 2 quoted market prices as follows (in thousands):


	Fair Value Measurements at
	December 31, 2024		December 31, 2023
Convertible Senior Notes due 2025	$	39,130	$	271,688
Convertible Senior Notes due 2029	407,752		*
Total fair value of outstanding convertible senior notes	$	446,882	$	271,688

* Not applicable as no notes were outstanding at this date.

- Definition

The entire disclosure for the fair value of financial instruments (as defined), including financial assets and financial liabilities (collectively, as defined), and the measurements of those instruments as well as disclosures related to the fair value of non-financial assets and liabilities. Such disclosures about the financial instruments, assets, and liabilities would include: (1) the fair value of the required items together with their carrying amounts (as appropriate); (2) for items for which it is not practicable to estimate fair value, disclosure would include: (a) information pertinent to estimating fair value (including, carrying amount, effective interest rate, and maturity, and (b) the reasons why it is not practicable to estimate fair value; (3) significant concentrations of credit risk including: (a) information about the activity, region, or economic characteristics identifying a concentration, (b) the maximum amount of loss the entity is exposed to based on the gross fair value of the related item, (c) policy for requiring collateral or other security and information as to accessing such collateral or security, and (d) the nature and brief description of such collateral or security; (4) quantitative information about market risks and how such risks are managed; (5) for items measured on both a recurring and nonrecurring basis information regarding the inputs used to develop the fair value measurement; and (6) for items presented in the financial statement for which fair value measurement is elected: (a) information necessary to understand the reasons for the election, (b) discussion of the effect of fair value changes on earnings, (c) a description of [similar groups] items for which the election is made and the relation thereof to the balance sheet, the aggregate carrying value of items included in the balance sheet that are not eligible for the election; (7) all other required (as defined) and desired information.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 55
-Paragraph 107
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482078/820-10-55-107

Reference 2: http://www.xbrl.org/2003/role/exampleRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 55
-Paragraph 100
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482078/820-10-55-100

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (c)(3)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482106/820-10-50-2

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 6A
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482106/820-10-50-6A

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2E
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482106/820-10-50-2E

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 6A
-Subparagraph (h)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482106/820-10-50-6A

Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 6A
-Subparagraph (f)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482106/820-10-50-6A

Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 6A
-Subparagraph (e)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482106/820-10-50-6A

Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 6A
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482106/820-10-50-6A

Reference 10: http://www.xbrl.org/2003/role/disclosureRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (h)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482106/820-10-50-2

Reference 11: http://www.xbrl.org/2003/role/disclosureRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (g)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482106/820-10-50-2

Reference 12: http://www.xbrl.org/2003/role/disclosureRef
-Topic 940
-SubTopic 820
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478119/940-820-50-1

+ Details

Stockholders' Equity -Shares of Common Stock Reserved for Future Issuance (Details) - shares	Dec. 31, 2024	May 31, 2023
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock reserved for future issuance (in shares)	20,208,000	2,602,184
Shares reserved for issuance upon conversion of Convertible Senior Notes
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock reserved for future issuance (in shares)	8,202,000
Shares underlying outstanding warrants
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock reserved for future issuance (in shares)	194,000
Shares underlying outstanding stock options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock reserved for future issuance (in shares)	3,527,000
Shares underlying unvested restricted stock units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock reserved for future issuance (in shares)	3,739,000
Shares authorized for issuance pursuant to awards granted under the ESPP
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock reserved for future issuance (in shares)	2,684,000
Shares authorized for future equity award grants
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock reserved for future issuance (in shares)	1,862,000

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

+ Details

Insider Trading Policies and Procedures	12 Months Ended
Insider Trading Policies and Procedures	Dec. 31, 2024
Insider Trading Policies and Procedures [Line Items]
Insider Trading Policies and Procedures Adopted	true

Business Segment and Geographic Information - Additional Information (Details)	12 Months Ended
	Dec. 31, 2024 segment market	Dec. 31, 2023	Dec. 31, 2022
Revenue, Major Customer [Line Items]
Number of operating segments \| segment	1
Number of geographical markets \| market	2
United States \| Revenue from Contract with Customer Benchmark \| Customer Concentration Risk
Revenue, Major Customer [Line Items]
Customers accounted for 10% or more	61.00%	64.00%	65.00%
Outside the United States \| Revenue from Contract with Customer Benchmark \| Customer Concentration Risk
Revenue, Major Customer [Line Items]
Customers accounted for 10% or more	96.00%	99.00%	96.00%

Stockholders' Equity - Additional Information (Details) $ / shares in Units, $ in Millions	1 Months Ended				12 Months Ended
	May 31, 2024 shares	Mar. 31, 2022	Feb. 28, 2022	Oct. 31, 2013	Dec. 31, 2024 USD ($) purchase_period shares	Dec. 31, 2023 USD ($) shares	Dec. 31, 2022 USD ($) $ / shares shares	Dec. 31, 2021 shares	May 31, 2023 shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares issued by each warrant (in shares)					1
Common stock reserved for future issuance (in shares)					20,208,000				2,602,184
Increase in common stock reserve for issuance (in shares)	3,000,000
Total stock-based compensation expense capitalized as part of cost of inventory \| $					$ 1.8	$ 2.0
Unrecognized compensation expense \| $					$ 121.0
Share-based payment arrangement, cost not yet recognized, period for recognition					1 year 10 months 24 days
Stock options granted					0	0
Weighted average grant date fair value - options (in dollars per share) \| $ / shares							$ 42.16
Share-based Payment Arrangement, Option
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Maximum term of stock options (in years)					10 years
Vesting period							3 years	4 years
Vesting period of remaining stock (in years)							2 years	3 years
Risk-free interest rate							2.70%
Dividend yield							0.00%
Expected volatility							72.00%
Expected term (in years)							5 years 9 months 18 days
Share-based Payment Arrangement, Option \| Tranche One
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock vested percentage							33.00%	25.00%
Unvested restricted stock units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period		3 years	4 years
RSU granted (in shares)					2,332,553	2,359,907	1,542,859
RSU's outstanding (in shares)					3,738,770	3,176,159	1,833,832	610,731
RSU vested in period, fair value \| $					$ 58.5	$ 21.2	$ 12.7
Unvested restricted stock units \| Tranche One
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock vested percentage		33.00%	25.00%
Unvested restricted stock units \| Tranche Two
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period		2 years	3 years
Performance-Based Restricted Stock Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
RSU granted (in shares)					151,660	110,074	53,662
RSU's outstanding (in shares)					151,660	92,308	48,139
Awards to be granted under the ESPP
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period					2 years
Maximum percentage that employee can contribute for purchase of common stock				15.00%
Offering period					2 years
Number of purchase periods \| purchase_period					4
Purchase period					6 months
Purchase of common stock under ESPP (in shares)					770,362	499,431	262,936
Proceeds from stock plans \| $					$ 12.2	$ 10.7	$ 12.7
Date of Offering \| Awards to be granted under the ESPP
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Purchase price of common stock on date of purchase				85.00%
Date of Purchase \| Awards to be granted under the ESPP
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Purchase price of common stock on date of purchase				85.00%

Organization and Basis of Presentation (Policies)	12 Months Ended
Organization and Basis of Presentation (Policies)	Dec. 31, 2024
Organization, Consolidation and Presentation of Financial Statements [Abstract]
The Company	The Company Tandem Diabetes Care, a global insulin delivery and diabetes technology company, manufactures and sells advanced automated insulin delivery systems that reduce the burden of diabetes management, while creating new possibilities for patients, their loved ones and healthcare providers. Tandem Diabetes Care, Inc. is incorporated in the state of Delaware. Unless the context requires otherwise, the terms the “Company” or “Tandem” refer to Tandem Diabetes Care, Inc., together with its wholly-owned subsidiaries. The Company manufactures, sells, and supports insulin pump products that are designed to address the evolving needs and preferences of differentiated segments of the insulin-dependent diabetes market. The Company recently expanded its insulin pump portfolio, which now includes both the t:slim X2 and the Tandem Mobi. Both pumps feature Control-IQ technology, which is the Company’s advanced algorithm for managing insulin delivery, using information received from integrated continuous glucose monitoring (CGM) sensors. New software for the insulin pumps may be updated remotely by the individual users as new advancements become available and are compatible with other complementary digital health offerings, such as the mobile application and cloud-based diabetes management applications. The Company’s insulin pump systems products are generally considered durable medical equipment and have an expected lifespan of at least four years. In addition to insulin pumps, the Company sells single-use components that are used together with the pumps and are replaced every few days, including cartridges for storing and delivering insulin, and infusion sets that connect the insulin pump to a user’s body.
Basis of Presentation and Principles of Consolidation	Basis of Presentation and Principles of Consolidation The Company has prepared the accompanying consolidated financial statements in accordance with accounting principles generally accepted in the United States of America, or U.S. GAAP. The statements include the accounts of Tandem Diabetes Care, Inc. and its wholly-owned subsidiaries. All significant intercompany balances and transactions have been eliminated in consolidation. The functional currency of the Company’s foreign subsidiaries is their respective local currency. The Company translates the financial statements of its foreign subsidiaries into U.S. dollars using period-end exchange rates for assets and liabilities and average exchange rates for each period for revenue, costs and expenses. Translation related adjustments are included in other comprehensive income (loss), and in accumulated other comprehensive income (loss) in the stockholders’ equity section of the Company’s consolidated balance sheets. Foreign exchange gains or losses resulting from balances denominated in a currency other than the functional currency are recognized in interest income and other, net in the Company’s consolidated statements of operations.
Use of Estimates	Use of Estimates The preparation of the consolidated financial statements in conformity with U.S. GAAP requires management to make estimates and judgments that affect the reported amounts of assets, liabilities, revenues and expenses and the disclosure of contingent assets and liabilities in the Company’s consolidated financial statements and accompanying notes as of the date of the consolidated financial statements. Some of those judgments can be subjective and complex, and therefore, actual results could differ materially from those estimates under different assumptions or conditions.
Cash Equivalents	Cash Equivalents The Company considers all highly liquid investments with a maturity of three months or less from the date of purchase and that can be liquidated without prior notice or penalty to be cash equivalents.
Short-Term Investments	Short-Term Investments The Company’s short-term investments are classified as available-for-sale securities. Such securities are carried at fair value as determined by prices for identical or similar securities at the balance sheet date. The Company’s short-term investments consist of Level 1 and Level 2 financial instruments in the fair value hierarchy. The net unrealized gains or losses on available-for-sale securities that are not related to credit factors are reported as a component of other comprehensive income (loss) within the statements of operations and accumulated other comprehensive income (loss) as a separate component of stockholders’ equity on the consolidated balance sheets. The Company determines realized gains or losses on the sale of available-for-sale securities using the specific identification method and includes net realized gains and losses as a component of other income or expense within the consolidated statements of operations. The Company reviews its available-for-sale debt securities for credit losses quarterly, considering a variety of factors, including the significance of the decline in value as compared to the amortized cost basis; underlying factors contributing to a decline in the prices of securities in a single asset class; the security’s relative performance versus its peers, sector or asset class; the market and economy in general; views of external investment managers; news or financial information that has been released specific to the investee; and the outlook for the overall industry in which the investee operates. Losses on available-for-sale debt securities as a result of credit factors are recognized by recording an impairment loss as a component of other income or expense within the consolidated statements of operations and a corresponding allowance for credit losses. The Company has not recognized any impairment losses related to its short-term investments during the years ended December 31, 2024, 2023 and 2022.
Accounts Receivable	Accounts Receivable The Company grants credit to various customers in the ordinary course of business and is paid directly by customers who use its products, distributors and third-party insurance payors. The Company maintains an allowance for its current estimate of expected credit losses. Provisions for expected credit losses are estimated based on historical experience, assessment of specific customer-related risks, review of outstanding invoices, forecasts about the future, and various other assumptions and estimates that are believed to be reasonable under the circumstances, including changes to credit risks as a result of recessionary concerns, changes in discretionary spending, increased interest rates, and other macroeconomic factors. Uncollectible accounts are written off against the allowance after appropriate collection efforts have been exhausted and when it is deemed that a balance is uncollectible.
Concentration of Credit Risk	Concentration of Credit Risk Financial instruments that potentially subject the Company to concentrations of credit risk consist primarily of cash, cash equivalents, short-term investments and accounts receivable. The Company maintains deposit accounts in federally insured financial institutions in excess of federally insured limits. The Company also maintains investments in money market funds that are not federally insured. Additionally, the Company has established guidelines regarding investment instruments and their maturities, which are designed to maintain preservation of principal and liquidity.
Valuation of Inventories	Valuation of Inventories Inventories are valued at the lower of cost or net realizable value, determined by the first-in, first-out method. Inventory is recorded using standard cost, including material, labor and overhead costs. The Company periodically reviews inventories for potential impairment and adjusts inventory for potentially excess or obsolete goods to state inventories at their net realizable value. Factors influencing these adjustments include quantities on hand and firm purchase commitments, expectations of future use, judgments based on quality control testing data and assessments of the likelihood of scrapping or obsoleting certain inventories based on future demand for its products and market conditions.
Long-Lived Assets	Long-Lived Assets Property and Equipment Property and equipment, which primarily consist of office furniture and equipment, manufacturing equipment, scientific equipment, computer equipment, and leasehold improvements, are stated at cost, less accumulated depreciation. Property and equipment are depreciated over the estimated useful lives of the assets, generally three to seven years, using the straight-line method. Leasehold improvements and related equipment are amortized over the lesser of the estimated useful lives of the assets or the remaining lease term, unless there is a transfer of title or purchase option that is reasonably certain to be exercised. Maintenance and repair costs are expensed as incurred.
Operating Lease Right-of-Use Assets and Liabilities	Operating Lease Right-of-Use Assets and Liabilities Operating lease right-of-use assets represent the Company’s right to use an underlying asset for the lease term and lease liabilities represent its obligation to make lease payments arising from the lease. Operating lease right-of-use assets and liabilities are recognized when the Company takes possession of the leased property (Commencement Date) based on the present value of lease payments over the lease term. For lease agreements that contain lease and non-lease components, the Company accounts for both of those components as a single lease component. Rent expense on noncancelable leases containing known future scheduled rent increases is recorded on a straight-line basis over the term of the respective leases beginning on the Commencement Date. The difference between rent expense and rent paid is accounted for as a component of operating lease right-of-use assets on the Company’s consolidated balance sheets. Landlord improvement allowances and other similar lease incentives are recorded as a reduction of the right-of-use leased assets, and are amortized on a straight-line basis as a reduction to operating lease costs.
Intangible Assets Subject to Amortization	Intangible Assets Subject to Amortization Finite-lived intangible assets are recorded at cost, net of accumulated amortization and, if applicable, impairment charges. Amortization of finite-lived intangible assets is recognized over their estimated useful lives on a straight-line basis.
Impairment of Long-Lived Assets	Impairment of Long-Lived Assets Long-lived assets, such as property and equipment, right-of-use lease assets, and acquired intangible assets subject to amortization, are reviewed for impairment whenever events or changes in circumstances indicate that the carrying amount of an asset may not be recoverable. If circumstances require a long-lived asset or asset group be tested for possible impairment, the Company first compares undiscounted cash flows expected to be generated by that asset or asset group to its carrying amount. If the carrying amount of the long-lived asset or asset group is not recoverable on an undiscounted cash flow basis, an impairment is recognized to the extent that the carrying amount exceeds its fair value. Fair value is determined using unobservable (Level 3) inputs, including discounted cash flow models, future estimated sublease income, and third-party independent appraisals, as considered necessary. There is uncertainty in the projected undiscounted future cash flows used in the Company’s impairment review analysis, which requires the use of estimates and assumptions. If actual performance does not achieve the projections, or if the assumptions used change in the future, the Company may be required to recognize additional impairment charges in future periods. Other than the impairment of operating lease right-of-use assets and related leasehold improvements and furniture and fixtures recognized in 2023 and 2022 (see Note 6, “Leases”), there were no impairments of long-lived assets, including acquired intangible assets, during the years ended December 31, 2024, 2023 and 2022.
Strategic Investments	Strategic Investments The Company measures strategic investments at cost minus impairment, if any, adjusted for changes in observable prices. Strategic investments are reviewed, on an individual basis, for impairment whenever significant events or changes in circumstances indicate that the carrying amount of the investment might not be recoverable. The Company held strategic equity investments totaling zero and $10.1 million in private investee companies at December 31, 2024 and December 31, 2023, respectively. In November 2024, the Company invested an additional $46.4 million cash in one of its private company investees, resulting in a change to equity method accounting, described below. During the year ended December 31, 2024, the Company also recorded an impairment charge of $2.0 million related to one of its strategic investments in a private investee company. The Company did not record any impairment charges related to its strategic investments during the years ended December 31, 2023 and 2022. The strategic investments were included as a component of other long-term assets on the consolidated balance sheet. From November 2023 to June 2024, the company held a strategic investment balance of $22.2 million in the form of subordinated convertible notes of one private investee company. The subordinated notes were converted into equity of the private investee company at final maturity, which occurred in June 2024. Equity Method Investments The Company held equity method investments of $74.5 million at December 31, 2024. We use the equity method to account for investments in companies if our investment provides us with the ability to exercise significant influence but not control over the operating and financial policies of the investee. The Company assesses significant influence by considering various factors, including the nature and magnitude of the investment, voting rights held and participation in the governance of the investee, if any. The Company may also consider additional relevant factors, such as the presence of other business relationships. In November 2024, the Company invested an additional $46.4 million cash in one of its private investee companies that was previously accounted for as a strategic investment at cost. As a result of the additional investment, the Company owned more than 20% of the private investee company’s outstanding equity and held significant influence but not control over the private investee company’s activities. As a result, the investment was accounted for using the equity method following the November 2024 transaction date. Our consolidated net loss included our Company’s proportionate share of the net loss of our equity method investee, which was a loss of $2.1 for the year ended December 31, 2024. For the years ended December 31, 2023 and 2022, the Company did not hold any equity method investments and therefore did not recognize a share of net income or loss from any equity method investments.
Revenue Recognition	Revenue Recognition Revenue is generated primarily from sales of insulin pumps, single-use insulin cartridges and infusion sets to individual customers with third-party insurance coverage and through a network of distributors that resell the products to insulin-dependent diabetes customers. The Company recognizes revenue when it transfers control of the promised goods or services to customers in an amount that reflects the consideration to which the Company expects to be entitled in exchange for those goods or services, net of estimated rebates and returns. Revenue Recognition for Arrangements with Multiple Performance Obligations The Company considers the individual deliverables in its product offerings to be separate performance obligations. The transaction price is determined based on the consideration expected to be received, based either on the stated value in contractual arrangements or the estimated cash to be collected in non-contracted arrangements. The Company allocates the consideration to the individual performance obligations and recognizes the consideration based on when the performance obligation is satisfied, considering whether or not this occurs at a point in time or over time. Generally, insulin pumps, cartridges, infusion sets, and accessories are deemed performance obligations that are satisfied at a point in time when the customer obtains control of the promised good, which typically is upon shipment for our distributor arrangements and upon receipt for sales directly to individual customers. Complementary products, such as the Company’s data management and software update platforms, are considered distinct performance obligations that are satisfied over time, as access and support for these products is provided throughout the typical four-year warranty period of the insulin pumps. Accordingly, revenue related to the complementary products is deferred and recognized over a four-year period. Where there is no standalone value for the complementary product, the Company determines its value by applying the expected cost plus a margin approach and then allocates the residual to the insulin pumps. Revenue Recognition for Tandem Choice Program In September 2022, the Company launched a technology access program referred to as Tandem Choice, that provided eligible, in-warranty t:slim X2 customers in the United States with the flexibility to obtain the newest hardware platform, Tandem Mobi, once commercially available. Participating customers had the right to purchase the alternative Tandem pump for a fee, referred to as a choice right. The Company determined that the program created a material right for which a portion of each t:slim X2 pump sales transaction price was allocated and deferred. The Company determined that the ability for a customer to upgrade to a new technology represents a material right because the pricing inherent in such option provided the customer with a discount that is incremental to the range of discounts that would otherwise be granted for the related goods and services to comparable customers. The standalone selling price for the choice right was estimated based on the adjusted market assessment approach and contemplated the likelihood that the respective option will be exercised. The Company began selling Tandem Mobi insulin pumps in the first quarter of 2024 and eligibility for the Tandem Choice program ended in February 2024. Consequently, the Company ceased allocating and deferring a portion of the transaction price for the material right for pumps sold after that date. Eligible customers who purchased a t:slim X2 insulin pump during the program period had until December 31, 2024 to exercise the option to switch to the Tandem Mobi for a stated fee. The Company recognized the deferred sales when the obligations under the Tandem Choice program were satisfied. If a customer elected to participate in the program, the Company recognized upgrade fees received, and the associated cost of goods sold at the time of fulfillment. Substantially all of the remaining deferrals were recognized at program expiration on December 31, 2024. For the year ended December 31, 2024, the Company recognized net revenue of $30.2 million as a result of the Tandem Choice program. Sales Rebates The Company is subject to certain rebates on pricing programs with managed care organizations, such as governmental and third-party commercial payors. The Company estimates provisions for rebates based on contractual arrangements, estimates of products sold subject to rebate, known events or trends and channel inventory data. Estimated sales rebates included in other long-term liabilities have an estimated payment due date beyond twelve months from the balance sheet date. Accordingly, actual rebates paid may differ from estimated amounts recorded in the accompanying consolidated financial statements. Sales Returns The Company offers a 90-day right of return to customers in the United States and Canada from the date of shipment of its insulin pumps, provided a physician’s confirmation of the medical reason for the return is received. Estimated allowances for sales returns are based on historical returned quantities as compared to pump shipments in those same periods of return, adjusted for known or expected changes in the marketplace when appropriate. Shipping and Handling Expenses Shipping and handling expenses associated with product delivery are included within cost of sales in the Company’s statements of operations. Amounts billed to a customer for shipping and handling are reported as revenues.
Warranty Reserve	Warranty Reserve The Company generally provides a four-year warranty on its insulin pumps to end-user customers and may replace any pumps that do not function as intended in accordance with the product specifications within the warranty period. In addition, the Company offers a six-month warranty on single-use insulin cartridges and infusion sets. Estimated warranty costs are recorded at the time of shipment, and the Company reevaluates the estimate of the warranty reserve obligation at each reporting period. Warranty costs are primarily estimated based on the current expected product replacement cost and expected replacement rates using historical experience. Returned insulin pumps may be refurbished and redeployed. Experience has shown that initial data for any new pump version or pump platform may be insufficient. Therefore, the Company relies on long-term historical replacement data from existing platforms until sufficient data is available. As actual experience accumulates, the Company adjusts its warranty reserve estimate accordingly. In addition, the availability of replacement data may differ by country due to local compliance and privacy regulations, which may require the Company to estimate its warranty liability using available information or data from similar markets. The Company may make further adjustments to the warranty reserve when appropriate, considering revised expectations of product performance based on enhanced hardware, or new features and capabilities that may become available through Tandem Device Updater. Warranty expense is recorded as a component of cost of sales in the consolidated statements of operations.
Stock-Based Compensation	Stock-Based Compensation Stock-based compensation cost is measured at the grant date based on the estimated fair value of the award, and the portion that is ultimately expected to vest is recognized as compensation expense over the requisite service period on a straight-line basis. The Company estimates the fair value of stock options issued under the Company’s stock incentive plans, and the fair value of employee purchase rights under the Company’s Employee Stock Purchase Plan (ESPP) using the Black-Scholes option pricing model on the date of grant. The Black-Scholes option pricing model requires the use of assumptions about a number of variables, including stock price volatility, expected term, dividend yield and risk-free interest rate (see Note 8, “Stockholders’ Equity”). The fair value of restricted stock unit (RSU) awards issued under the Company’s stock incentive plans that vest solely based on service, is estimated based on the fair market value of the underlying stock on the date of grant. The fair value of RSU awards that vest based upon the Company’s actual performance relative to predefined performance metrics and the awardee’s continuing service through the measurement date is generally estimated based on the fair market value of the underlying stock on the date of grant and the probability that the specified performance criteria will be met. At each reporting period, the Company reassesses the probability of the achievement of such performance metrics. Any expense change resulting from an adjustment in the estimated shares to be released is recorded in the period of adjustment.
Research and Development Costs	Research and Development Costs All research and development costs are charged to expense as incurred. Such costs include personnel-related costs, including stock-based compensation, supplies, license fees, development prototypes, outside design and testing services, depreciation, allocated facilities and information services, clinical trial costs, milestone payments under the Company’s licensing, development and commercialization agreements, and other indirect costs. Acquired In-Process Research and Development Expenses Acquired in-process research and development (IPR&D) expenses reflect the costs of externally developed IPR&D projects acquired directly in a transaction other than a business combination that do not have an alternative future use, including the initial costs of rights to IPR&D projects. The acquired IPR&D is expensed on acquisition date. Future costs to develop these IPR&D projects are recorded in research and development expenses on the consolidated statements of operations as incurred.
Income Taxes	Income Taxes The Company uses the asset and liability method of accounting for income taxes. Deferred tax assets or liabilities are recognized based on the temporary differences between financial statement and income tax bases of assets and liabilities using enacted tax rates in effect for the years in which the differences are expected to reverse. Tax law and rate changes are reflected in income in the period such changes are enacted. A valuation allowance is recorded when it is more likely than not that some of the deferred tax assets will not be realized. The evaluation of the need for a valuation allowance is performed on a jurisdiction-by-jurisdiction basis, and includes a review of all available positive and negative evidence. Factors reviewed include projections of pre-tax book income for the foreseeable future, determination of cumulative pre-tax book income after permanent differences, earnings history, and reliability of forecasting. The Company will continue to assess the need for a valuation allowance on its deferred tax assets by evaluating both positive and negative evidence that may exist. Any adjustment to the net deferred tax asset valuation allowance would be recorded in the consolidated statement of operations for the period that the adjustment is determined to be required. The Company’s income tax returns are based on calculations and assumptions that are subject to examination by the Internal Revenue Service and other tax authorities. In addition, the calculation of the Company’s tax liabilities involves dealing with uncertainties in the application of complex tax regulations. The Company recognizes liabilities for uncertain tax positions using a two-step approach. The first step is to evaluate the tax position for recognition by determining if the weight of available evidence indicates that it is more likely than not that the position will be sustained on audit, including resolution of related appeals or litigation processes, if any. The second step is to measure the tax benefit as the largest amount that is more than 50% likely to be realized upon settlement. While the Company believes it has appropriate support for the positions taken on its tax returns, the Company regularly assesses the potential outcomes of examinations by tax authorities in determining the adequacy of its provision for income taxes. The Company continually assesses the likelihood and amount of potential revisions and adjusts the income tax provision, income taxes payable and deferred taxes in the period in which the facts that give rise to a revision become known. The Company includes interest and penalties related to income taxes, including unrecognized tax benefits, within income tax expense.
Comprehensive Loss	Comprehensive Loss All components of comprehensive loss, including net loss, are reported in the consolidated financial statements in the period in which they are recognized. Comprehensive loss is defined as the change in equity during a period from transactions and other events and circumstances from non-owner sources, including unrealized gains and losses on marketable securities and foreign currency translation adjustments.
Net Loss Per Share	Net Loss Per Share Basic net loss per share is calculated by dividing the net loss by the weighted average number of common shares outstanding for the period, without consideration for common stock equivalents. Diluted net loss per share reflects the potential dilution that would occur if securities exercisable for or convertible into common stock were exercised for or converted into common stock. Dilutive common share equivalents are comprised of stock options and unvested RSUs outstanding under the Company’s stock incentive plans, potential awards to be granted pursuant to the ESPP, and common stock warrants, each calculated using the treasury stock method, and shares issuable upon conversion of the convertible senior notes calculated using the if-converted method.
Recently Issued Accounting Pronouncements and Accounting Pronouncements Issued and Not Yet Adopted	Recently Issued Accounting Pronouncements In November 2023, the FASB issued ASU 2023-07 to improve the information that a public entity discloses about reportable segments and to address investor requests for more information about reportable segment expenses. The pronouncement requires a public entity to report a measure of segment profit or loss that the chief operating decision maker (CODM) uses to assess segment performance and make decisions about allocating resources. ASU 2023-07 also requires other specified segment items and amounts, such as depreciation, amortization, and depletion expense, to be disclosed under certain circumstances. The amendments in ASU 2023-07 are effective for fiscal years beginning after December 15, 2023 and interim periods within fiscal years beginning after December 15, 2024, adopted retrospectively. The Company’s adoption of ASU 2023-07 did not have a material impact on the Company’s consolidated financial statements or disclosures. Accounting Pronouncements Issued and Not Yet Adopted In November 2024, the FASB issued ASU 2024-03 Income Statement–Reporting Comprehensive Income–Expense Disaggregation Disclosures (Subtopic 220-40): Disaggregation of Income Statement Expenses (ASU 2024-03), which requires entities to disclose information about purchases of inventory, employee compensation, and intangible asset amortization in each income statement line item that contains those expenses. ASU 2024-03 is effective for annual reporting periods beginning after December 15, 2026 and interim reporting periods beginning after December 15, 2027. Early adoption is permitted. The Company is currently evaluating ASU 2024-03 to determine the impact it may have on its consolidated financial statements. In December 2023, the FASB issued ASU 2023-09 Income Taxes (Topic 740): Improvements to Income Tax Disclosures, which requires the Company to disclose disaggregated jurisdictional and categorical information for the tax rate reconciliation, income taxes paid and other income tax related amounts. The guidance is effective for annual periods beginning after December 15, 2024, with early adoption permitted. The Company is currently evaluating ASU 2023-09 to determine the impact it may have on its consolidated financial statements.
Fair Value of Financial Instruments	Fair Value of Financial Instruments The carrying amounts of cash and cash equivalents, accounts receivable, accounts payable, accrued expenses, and employee-related liabilities are reasonable estimates of their fair values because of the short-term nature of these assets and liabilities. Short-term investments are carried at fair value. In March 2024, the Company issued $316.3 million aggregate principal amount of the Company’s Convertible Senior Notes Due 2029, and repurchased $246.7 million of principal of the Company’s Convertible Senior Notes due 2025 (see Note 7, “Debt”).
Segment Reporting	Segment Reporting Operating segments are identified as components of an enterprise about which discrete financial information is available for evaluation by the chief operating decision-maker (CODM) in making decisions regarding resource allocation and assessing performance. The Company is organized based on its current product portfolio, which consists primarily of insulin pumps, single-use insulin cartridges and infusion sets for the storage and delivery of insulin. The Company views its operations and manages its business as one reporting segment because key operating decisions and resource allocations are made by the CODM using consolidated financial data. Accordingly, the Company is organized as a single operating segment and therefore a single reportable segment: Insulin Pumps and Supplies. The Company’s CODM is the Chief Executive Officer (CEO), who evaluates segment performance based on segment net income (loss) on a consolidated basis. Segment net income (loss) was consistent with the net loss amounts reported in the Company’s consolidated statement of operations and comprehensive loss for the years ended December 31, 2024, 2023, and 2022. There were no significant segment expenses that are regularly provided to the CODM other than those reported in the Company’s consolidated statement of operations and comprehensive loss for the years ended December 31, 2024, 2023, and 2022. The Company’s CODM is provided segment assets information on a consolidated basis for the evaluation of company performance. Total segment assets were consistent with total assets reported in the Company’s consolidated balance sheets for December 31, 2024 and 2023, respectively.

Summary of Significant Accounting Policies - Reconciliation of Change in Estimated Warranty Liabilities (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Movement in Standard and Extended Product Warranty Accrual, Increase (Decrease) [Roll Forward]
Balance at beginning of the period	$ 37,173	$ 36,537	$ 30,401
Provision for warranties issued during the period	48,938	35,690	32,699
Settlements made during the period	(36,632)	(32,617)	(25,447)
Increases (decreases) in warranty estimates	1,929	(2,437)	(1,116)
Balance at end of the period	51,408	37,173	36,537
Other current liabilities	31,048	18,135
Other long-term liabilities	20,360	19,038
Total warranty reserve	$ 51,408	$ 37,173	$ 36,537

Summary of Significant Accounting Policies - Total Estimated Sales Rebates (Details) - USD ($) $ in Thousands	Dec. 31, 2024	Dec. 31, 2023
Accounting Policies [Abstract]
Other current liabilities	$ 2,229	$ 505
Other long-term liabilities	7,167	8,042
Total sales rebate	$ 9,396	$ 8,547

Audit Information	12 Months Ended
Audit Information	Dec. 31, 2024
Audit Information [Abstract]
Auditor Firm ID	42
Auditor Name	Ernst & Young LLP
Auditor Location	San Diego, California

Leases - Additional Information (Details)	12 Months Ended
Leases - Additional Information (Details)	Dec. 31, 2024 USD ($)	Dec. 31, 2023 USD ($)	Dec. 31, 2022 USD ($)	Sep. 30, 2021 ft² extension
Lessee, Lease, Description [Line Items]
Thereafter	$ 76,891,000
Operating lease impairment charge	0	$ 0	$ 0
Headquarters Lease
Lessee, Lease, Description [Line Items]
Area of office space leased \| ft²				181,949
Operating lease, number of options to extend \| extension				2
Headquarters Lease Phase I
Lessee, Lease, Description [Line Items]
Area of office space leased \| ft²				143,850
Operating lease extension period				5 years
Headquarters Lease Phase II
Lessee, Lease, Description [Line Items]
Area of office space leased \| ft²				38,099
Operating lease, liability to be paid 2025 through 2028	2,200,000
Thereafter	$ 23,200,000
Vista Sorrento Lease \| Lease Agreements
Lessee, Lease, Description [Line Items]
Operating lease impairment charge		14,100,000
Operating lease, impairment loss		11,200,000
Write-off of fixed assets		$ 2,900,000
Minimum
Lessee, Lease, Description [Line Items]
Lease term	2 years
Maximum
Lessee, Lease, Description [Line Items]
Lease term	13 years

Income Taxes - Income (Loss) Before Provision for Income Taxes (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Income Tax Disclosure [Abstract]
United States	$ (78,156)	$ (135,411)	$ (94,033)
Foreign	(13,714)	(84,843)	1,181
Loss before income taxes	$ (91,870)	$ (220,254)	$ (92,852)

- Definition

Amount of income (loss) from continuing operations, including income (loss) from equity method investments, before deduction of income tax expense (benefit), and income (loss) attributable to noncontrolling interest.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 22
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482810/280-10-50-22

Reference 2: http://www.xbrl.org/2003/role/exampleRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 55
-Paragraph 48
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482785/280-10-55-48

Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 32
-Subparagraph (f)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482810/280-10-50-32

Reference 4: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 30
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482810/280-10-50-30

Reference 5: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 270
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (i)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482964/270-10-50-1

Reference 6: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 32
-Subparagraph (ee)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482810/280-10-50-32

Reference 7: http://fasb.org/us-gaap/role/ref/otherTransitionRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 32
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482810/280-10-50-32

Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Topic 944
-SubTopic 220
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-04(11))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477250/944-220-S99-1

Reference 9: http://www.xbrl.org/2003/role/exampleRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 31
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482810/280-10-50-31

Reference 10: http://www.xbrl.org/2003/role/disclosureRef
-Topic 942
-SubTopic 235
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-05(b)(2))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477314/942-235-S99-1

Reference 11: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 220
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03(10))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147483621/220-10-S99-2

Reference 12: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 942
-SubTopic 220
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-04(15))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478524/942-220-S99-1

+ Details

Summary of Significant Accounting Policies (Tables)

12 Months Ended

Dec. 31, 2024

Accounting Policies [Abstract]

Schedule of Customers Accounted for 10% or More

The following table summarizes the percentages of total sales and accounts receivable, net for customers who accounted for 10% or more of the respective amounts for the periods presented:


	Total Sales						Accounts Receivable, net
	Year Ended December 31,						December 31,
	2024		2023		2022		2024		2023
Distributor A	11.2	%	12.2	%	11.6	%	11.1	%	10.0	%
Distributor B	*		*		*		*		10.5	%
Distributor C	*		*		*		11.8	%	10.6	%
Distributor D	11.5	%	10.8	%	14.4	%	11.2	%	11.5	%

* Amount related to the respective customer represented less than 10% for the period presented.

Schedule of Estimated Sales Rebates

As of December 31, 2024 and December 31, 2023, total estimated sales rebates were included in the following consolidated balance sheet accounts (in thousands):


	December 31, 2024		December 31, 2023
Other current liabilities	$	2,229	$	505
Other long-term liabilities	7,167		8,042
Total sales rebate	$	9,396	$	8,547

Schedule of Reconciliation of Change in Estimated Warranty Liabilities

The following table provides a reconciliation of the changes in product warranty liabilities for the years ended December 31, 2024, 2023 and 2022 (in thousands):


	Year Ended December 31,
		2024		2023		2022
Balance at beginning of the period		$	37,173	$	36,537	$	30,401
Provision for warranties issued during the period		48,938		35,690		32,699
Settlements made during the period		(36,632)		(32,617)		(25,447)
Increases (decreases) in warranty estimates		1,929		(2,437)		(1,116)
Balance at end of the period		$	51,408	$	37,173	$	36,537

As of December 31, 2024 and December 31, 2023, total product warranty reserves were included in the following consolidated balance sheet accounts (in thousands):


	December 31, 2024		December 31, 2023

Other current liabilities	$	31,048	$	18,135
Other long-term liabilities	20,360		19,038
Total warranty reserve	$	51,408	$	37,173

Schedule of Anti-Dilutive Securities


	Year Ended December 31,
		2024	2023	2022
Options to purchase common stock		124	135	1,138
Unvested restricted stock units		2,858	2,089	1,118
Warrants to purchase common stock		194	194	194
Awards granted under the ESPP		58	14	8
Convertible senior notes (if-converted)		8,202	2,554	2,554
		11,436	4,986	5,012

Debt

12 Months Ended

Dec. 31, 2024

Debt Disclosure [Abstract]

Debt

Convertible Senior Notes Due 2029

On March 8, 2024, the Company completed an offering of $316.3 million aggregate principal amount of 1.50% Convertible Senior Notes due 2029 (the 2029 Notes). The proceeds from the issuance of the 2029 Notes were $306.8 million, net of debt issuance costs. The Company used approximately $246.1 million of the net proceeds to repurchase approximately $246.7 million in aggregate principal amount of its Convertible Senior Notes Due 2025 (the 2025 Notes) concurrently with the pricing of the 2029 Notes in privately negotiated transactions.

The Company also paid $1.3 million of accrued interest due at time of the note repurchase. As a result of the repurchase, the Company recognized a $1.3 million loss on extinguishment of debt in the consolidated statement of operations for the year ended December 31, 2024. The loss on extinguishment of debt included the unamortized debt issuance costs related to the portion of the 2025 Notes repurchased.

The Company used $30.0 million of the net proceeds to repurchase shares of the Company’s common stock from certain purchasers of the 2029 Notes at a purchase price equal to the last reported sale price per share of the Company’s common stock on March 5, 2024, which was $27.105 per share. In addition, the Company used $15.8 million of the net proceeds to pay the cost of the capped call transactions (2029 Capped Call Transactions) discussed below.

The 2029 Notes are the Company’s senior unsecured obligations. Interest is payable in cash semi-annually in arrears on March 15 and September 15 of each year beginning on September 15, 2024, at a rate of 1.50% per year. The 2029 Notes mature on March 15, 2029 unless repurchased, redeemed, or converted in accordance with their terms prior to the maturity date.

The initial conversion rate for the 2029 Notes is 28.9361 shares of common stock per $1,000 principal amount of the 2029 Notes, which is equivalent to an initial conversion price of approximately $34.56 per share of the Company’s common stock (2029 Notes Conversion Price). The conversion rate is subject to customary adjustments for certain events as described in the indenture governing the 2029 Notes.

The Company may not redeem the 2029 Notes before March 22, 2027. The Company has the option to redeem for cash all or any portion of the 2029 Notes on or after March 22, 2027 if the last reported sale price of the Company’s common stock has been at least 130% of the 2029 Notes Conversion Price then in effect for at least 20 trading days (whether or not consecutive), including the trading day immediately preceding the date on which the Company provides notice of redemption, during any 30 consecutive trading day period, at a redemption price equal to 100% of the principal amount of the 2029 Notes to be redeemed, plus accrued and unpaid interest. No sinking fund is provided for the 2029 Notes.

Holders of the 2029 Notes may convert all or a portion of their 2029 Notes at their option before December 15, 2028, in multiples of $1,000 principal amounts, only under the following circumstances:

•during any calendar quarter commencing after the quarter ending on June 30, 2024 (and only during such calendar quarter), if the last reported sale price of the Company’s common stock, for at least 20 trading days (whether or not consecutive) during a period of 30 consecutive trading days ending on, and including, the last trading day of the immediately preceding calendar quarter is greater than or equal to 130% of the 2029 Notes Conversion Price on each applicable trading day;

•during the five business day period after any ten consecutive trading day period (the measurement period) in which the trading price per $1,000 principal amount of the 2029 Notes for each trading day of the measurement period was less than 98% of the product of the last reported sale price of the Company’s common stock and the applicable conversion rate of the 2029 Notes on such trading day;

•if the Company calls such 2029 Notes for redemption, at any time before the close of business on the scheduled trading day immediately preceding the redemption date, but only with respect to the 2029 Notes called (or deemed called) for redemption; or

•on the occurrence of specified corporate events.

On or after December 15, 2028, until the close of business on the second scheduled trading day immediately preceding the maturity date, holders may convert their 2029 Notes, in integral multiples of $1,000 principal amount, at any time, regardless of the foregoing circumstances. Upon conversion, the Company will pay or deliver, as the case may be, cash, shares of common stock or a combination of cash and shares of common stock, at the Company’s election, in the manner and subject to the terms and conditions provided in the indenture governing the 2029 Notes.

Convertible Senior Notes Due 2025

In May 2020, the Company completed an offering of $287.5 million aggregate principal amount of 1.50% Convertible Senior Notes due 2025 (the 2025 Notes). The proceeds from the issuance of the Notes were $244.6 million, net of debt issuance costs and cash used to pay the cost of the capped call transactions (Capped Call Transactions) discussed below.

In March 2024, the Company repurchased for cash $246.7 million aggregate principal amount of the 2025 Notes, concurrently with the pricing of the 2029 Notes in privately negotiated transactions.

The 2025 Notes are the Company’s senior unsecured obligations. Interest is payable in cash semi-annually in arrears beginning on November 1, 2020 at a rate of 1.50% per year. The 2025 Notes mature on May 1, 2025 unless repurchased, redeemed, or converted in accordance with their terms before the maturity date. As of December 31, 2024 the outstanding balance of the 2025 Notes was classified in current liabilities on the Company’s consolidated balance sheet.

The 2025 Notes are convertible into cash, shares of the Company’s common stock, or a combination of cash and shares of the Company’s common stock, at the Company’s election, at an initial conversion rate of 8.8836 shares of common stock per $1,000 principal amount of the 2025 Notes, which is equivalent to an initial conversion price of $112.57 (2025 Notes Conversion Price) per share of the Company’s common stock. The conversion rate is subject to customary adjustments for certain events as described in the indenture governing the 2025 Notes.

The Company has the option to redeem for cash all or any portion of the 2025 Notes on or after May 6, 2023 if the last reported sale price of the Company’s common stock has been at least 130% of the 2025 Notes Conversion Price then in effect for at least 20 trading days (whether or not consecutive), including the trading day immediately preceding the date on which the Company provides notice of redemption, during any 30 consecutive trading day period, at a redemption price equal to 100% of the principal amount of the 2025 Notes to be redeemed, plus accrued and unpaid interest. No sinking fund is provided for the 2025 Notes.

Holders of the 2025 Notes had the right to convert all or a portion of their 2025 Notes at their option before November 1, 2024, in multiples of $1,000 principal amounts, under certain circumstances outlined in the offering agreement.

From November 1, 2024, until the close of business on the second scheduled trading day immediately preceding the maturity date, holders may convert their Notes at any time, regardless of the foregoing circumstances. Upon conversion, the Company will pay or deliver, as the case may be, cash, shares of common stock or a combination of cash and shares of common stock, at the Company’s election, in the manner and subject to the terms and conditions provided in the indenture governing the 2025 Notes.

Holders of the 2025 Notes who convert in connection with a make-whole fundamental change or in connection with a redemption are entitled to an increase in the conversion rate. Additionally, in the event of a fundamental change, holders of the 2025 Notes may require us to repurchase all or a portion of the 2025 Notes at a price equal to 100% of the principal amount of the Notes, plus any accrued and unpaid interest.

The net carrying amount of the Company’s convertible senior notes on the consolidated balance sheets consisted of the following (in thousands):


	December 31, 2024		December 31, 2023
Principal amount:
Convertible Senior Notes Due 2025	$	40,760	$	287,500
Convertible Senior Notes Due 2029	316,250		*
Total principal amount	357,010		287,500
Unamortized debt issuance costs	(8,074)		(2,465)
Total debt, net	$	348,936	$	285,035
Less: current portion	(40,670)		—
Long-term senior convertible notes	$	308,266	$	285,035

* Not applicable as no notes were outstanding at this date.

As of December 31, 2024 and December 31, 2023, the if-converted value of the 2025 Notes did not exceed the principal amount. As of December 31, 2024, the if-converted value of the 2029 Notes exceeded the principal amount by $13.4 million.

In October 2023, the Company was notified that additional interest beyond the 1.50% per annum had been accruing on the 2025 Notes since May 2021, under the terms of the indenture. This additional interest accrued at a rate of 0.50% per annum on the outstanding principal amount of the Notes to approximately $3.3 million. The additional accrued interest was fully paid during the fourth quarter of 2023.

The following table summarizes the effective interest rates for each of our convertible senior notes for the periods shown:


	Year Ended December 31,
		2024		2023		2022
Effective interest rate:
Convertible Senior Notes Due 2025		2.1	%	2.2	%	2.2	%
Convertible Senior Notes Due 2029		2.1	%	*		*

* Not applicable as no notes were outstanding at this date.

The following table details interest expense related to the Notes recognized for the years ended December 31, 2024, and 2023 (in thousands):


	Year Ended December 31,
		2024		2023		2022
Contractual interest expense(1)		$	5,161	$	7,565	$	4,313
Amortization of debt issuance costs		1,906		1,803		1,896

Total interest expense		$	7,067	$	9,368	$	6,209

(1) Contractual interest expense for the year ended December 31, 2023 included $3.3 million of additional interest as discussed above.

2029 Capped Call Transactions

In connection with the issuance of the 2029 Notes, the Company entered into Capped Call Transactions in March 2024 with certain counterparties at a net cost of $15.8 million (2029 Capped Call Transactions). The 2029 Capped Call Transactions are expected generally to reduce potential dilution to the Common Stock upon any conversion of the 2029 Notes and/or offset any cash payments the Company is required to make in excess of the principal amount of converted 2029 Notes, as the case may be, with such reduction and/or offset subject to a cap based on a cap price initially equal to $42.0128 per share, and is subject to certain adjustments under the terms of the 2029 Capped Call Transactions.

2025 Capped Call Transactions

In connection with the issuance of the 2025 Notes, the Company entered into Capped Call Transactions in May 2020 with certain counterparties at a net cost of $34.1 million (2025 Capped Call Transactions). The 2025 Capped Call Transactions are expected generally to reduce potential dilution to the Common Stock upon any conversion of the 2025 Notes and/or offset any cash payments the Company is required to make in excess of the principal amount of converted 2025 Notes, as the case may be, with such reduction or offset subject to a cap. The cap price of the 2025 Capped Call Transactions is initially $173.18 per share of the Company’s common stock, and is subject to certain adjustments under the terms of the 2025 Capped Call Transactions.

In connection with the repurchase of certain 2025 Notes, the Company entered into unwind agreements with the existing option counterparties on March 5, 2024 to terminate a portion of the existing 2025 Capped Call Transactions in a notional amount corresponding to the amount of 2025 Notes repurchased (the Unwind Transactions). In connection with the Unwind Transactions, the Company received $0.2 million in cash as a termination payment in respect of the portion of the existing 2025 Capped Call Transactions that were unwound. The amount received was based generally on the termination values of the unwound portions of the existing 2025 Capped Call Transactions.

For accounting purposes, each of the capped call transactions described above are separate transactions, and not part of the terms of the 2029 Notes or the 2025 Notes. As these transactions met certain criteria under the applicable accounting guidance, each of the capped call transactions were recorded in stockholders’ equity and were not accounted for as derivatives. The cost of the transactions was recorded as a reduction of the Company’s additional paid-in capital in the Company’s consolidated balance sheet and will not be remeasured.

Promissory Note Payable

In connection with the acquisition of Capillary Biomedical, Inc. (see Note 12, “Acquisitions”), the Company assumed a $4.7 million promissory note payable. The promissory note accrues interest at the rate of 5.0% per year, and becomes due and payable upon the first sale or license of the commercialized product. At December 31, 2024 and 2023, the loan balance of $4.8 million and $4.7 million, respectively, was included as a component of other long-term liabilities on the consolidated balance sheets.

- Definition

The entire disclosure for information about short-term and long-term debt arrangements, which includes amounts of borrowings under each line of credit, note payable, commercial paper issue, bonds indenture, debenture issue, own-share lending arrangements and any other contractual agreement to repay funds, and about the underlying arrangements, rationale for a classification as long-term, including repayment terms, interest rates, collateral provided, restrictions on use of assets and activities, whether or not in compliance with debt covenants, and other matters important to users of the financial statements, such as the effects of refinancing and noncompliance with debt covenants.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 6
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481544/470-10-50-6

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 6
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481544/470-10-50-6

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 405
-SubTopic 40
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477092/405-40-50-1

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 405
-SubTopic 40
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (a)(3)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477092/405-40-50-1

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Topic 405
-SubTopic 40
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (a)(2)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477092/405-40-50-1

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Topic 405
-SubTopic 40
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (a)(1)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477092/405-40-50-1

Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Topic 405
-SubTopic 40
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477092/405-40-50-1

Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1B
-Subparagraph (h)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481139/470-20-50-1B

Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Topic 235
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08(c))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480678/235-10-S99-1

Reference 10: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 470
-Name Accounting Standards Codification
-Publisher FASB
-URI https://asc.fasb.org/470/tableOfContent

Reference 11: http://www.xbrl.org/2003/role/disclosureRef
-Topic 835
-SubTopic 30
-Name Accounting Standards Codification
-Section 45
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482925/835-30-45-2

Reference 12: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1B
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481139/470-20-50-1B

Reference 13: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1B
-Subparagraph (g)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481139/470-20-50-1B

Reference 14: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1B
-Subparagraph (i)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481139/470-20-50-1B

Reference 15: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1C
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481139/470-20-50-1C

Reference 16: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1C
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481139/470-20-50-1C

Reference 17: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1C
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481139/470-20-50-1C

Reference 18: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1E
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481139/470-20-50-1E

Reference 19: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1I
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481139/470-20-50-1I

Reference 20: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1I
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481139/470-20-50-1I

Reference 21: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1I
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481139/470-20-50-1I

+ Details

Commitments and Contingencies (Details) $ in Millions	Dec. 31, 2024 USD ($)
Commitments and Contingencies Disclosure [Abstract]
Unsecured letter of credit outstanding	$ 4.9
Purchase obligation	197.1
Purchase obligation due within one year	$ 192.7

Short-Term Investments

12 Months Ended

Dec. 31, 2024

Investments, Debt and Equity Securities [Abstract]

Short-Term Investments

The Company invests in marketable securities primarily consisting of debt instruments of the United States Government, United States Government-sponsored enterprises, and financial institutions and corporations with strong credit ratings. The following represents a summary of the estimated fair value of short-term investments at December 31, 2024 and December 31, 2023 (in thousands):


At December 31, 2024	Amortized Cost		Gross Unrealized Gain		Gross Unrealized Loss		Estimated Fair Value
Available-for-sale securities:
United States Government-sponsored enterprises	$	133,139	$	275	$	(134)	$	133,280
United States Treasury securities	103,645		197		(140)		103,702
Commercial paper	23,225		39		—		23,264
Corporate debt securities	105,635		248		(47)		105,836
Foreign government bonds	3,013		—		—		3,013

Total	$	368,657	$	759	$	(321)	$	369,095


At December 31, 2023	Amortized Cost		Gross Unrealized Gain		Gross Unrealized Loss		Estimated Fair Value
Available-for-sale securities:
United States Government-sponsored enterprises	$	181,851	$	518	$	(215)	$	182,154
United States Treasury securities	114,714		318		(28)		115,004
Commercial paper	72,505		33		(27)		72,511
Corporate debt securities	39,225		156		(6)		39,375

Total	$	408,295	$	1,025	$	(276)	$	409,044

The contractual maturities of available-for-sale debt securities as of December 31, 2024, were as follows (in thousands):


	Years to Maturity
At December 31, 2024	Within One Year		One to Two Years		Two to Three Years		Estimated Fair Value
United States Government-sponsored enterprises	$	44,717	$	39,193	$	49,370	$	133,280
United States Treasury securities	85,400		17,307		995		103,702
Commercial paper	23,264		—		—		23,264
Corporate debt securities	60,514		45,322		—		105,836
Foreign government bonds	—		—		3,013		3,013

Total	$	213,895	$	101,822	$	53,378	$	369,095

The Company has classified all marketable securities, regardless of maturity, as short-term investments based upon the Company’s ability and intent to use any of those marketable securities to satisfy the Company’s liquidity requirements.

The Company reviews the portfolio of available-for-sale debt securities quarterly to determine if any investment is impaired due to changes in credit risk or other potential valuation concerns. Unrealized losses on available-for-sale debt securities at December 31, 2024 were primarily due to an increase in market interest rates after certain debt securities were purchased, and the balance was not material to the Company’s quarterly results.

Fourth Quarter Financial Data (Unaudited)

12 Months Ended

Dec. 31, 2024

Quarterly Financial Information Disclosure [Abstract]

Fourth Quarter Financial Data (Unaudited)

The financial information for the three months ended December 31, 2024 and 2023 presented in the following table reflects all normal recurring adjustments that are, in the opinion of management, necessary for a fair statement of the results of the interim periods (in thousands, except per share data):


	For the Quarter Ended
	December 31, 2024		December 31, 2023
Sales(1)	$	282,648	$	196,796
Gross profit(1)(2)	$	157,455	$	93,295
Operating expenses	$	158,036	$	128,355
Operating loss	$	(581)	$	(35,060)
Net income (loss)	$	755	$	(30,002)
Basic net income (loss) per share	$	0.01	$	(0.46)
Weighted average shares used to compute basic net income (loss) per share	65,939		65,369
Diluted net income (loss) per share	$	0.01	$	(0.46)
Weighted average shares used to compute diluted net income (loss) per share	66,157		65,369

(1) The Company recognized revenue of $30.2 million and deferred revenue of $25.1 million for the quarters ended December 31, 2024 and 2023, respectively, as a result of the Tandem Choice program (see Note 2, “Summary of Significant Accounting Policies”).

(2) For the quarter ended December 31, 2024, the Company recognized charges to cost of sales of $0.6 million for Tandem Choice fulfillments in 2024, with no corresponding charge in 2023.

The numerator and denominator of the basic and diluted net income per share computations are calculated as follows for the three months ended December 31, 2024 (in thousands).


	For the Quarter Ended
	December 31, 2024


Net income - basic and diluted	$	754

Weighted average shares outstanding - basic	65,939
Dilutive common share equivalents:
Options to purchase common stock	112

Warrants to purchase common stock	59
Awards to be granted under the ESPP	47

Weighted average shares outstanding - diluted	66,157

Stockholders' Equity (Tables)

12 Months Ended

Dec. 31, 2024

Equity [Abstract]

Schedule of Shares of Common Stock Reserved for Future Issuance

The following shares of the Company's common stock were reserved for future issuance at December 31, 2024 (in thousands):


Shares reserved for issuance upon conversion of Convertible Senior Notes			8,202
Shares underlying outstanding warrants			194
Shares underlying outstanding stock options			3,527
Shares underlying unvested restricted stock units			3,739
Shares authorized for issuance pursuant to awards granted under the ESPP			2,684
Shares authorized for future equity award grants			1,862
Total			20,208

Schedule of Stockholders' Equity Common Stock Warrants

Warrants outstanding to purchase shares of the Company's common stock as of December 31, 2024 were as follows:

Issue Date

Exercise Price Per Share

Warrants Outstanding

Expiration Date of Warrants Outstanding

March 2017

$23.50

193,788

March 2027

Schedule of Stock Option Activities for 2006 Plan and 2013 Plan

The following table summarizes stock option activities under the Company’s stock incentive plans:


	Total Stock Options	Weighted- Average Exercise Price Per Share		Weighted- Average Remaining Contractual Life (in years)	Aggregate Intrinsic Value (in thousands)
Outstanding at December 31, 2021	4,814,846	$	57.08	7.07	$	452,081
Granted	83,008	$	65.28
Exercised	(280,275)	$	32.58		$	13,473
Canceled/forfeited/expired	(175,266)	$	77.93		$	2,143
Outstanding at December 31, 2022	4,442,313	$	57.95	6.12	$	30,236
Granted	—	$	—
Exercised	(72,536)	$	17.86		$	1,400
Canceled/forfeited/expired	(473,773)	$	90.14		$	95
Outstanding at December 31, 2023	3,896,004	$	54.79	5.30	$	11,703
Granted	—	$	—
Exercised	(112,171)	$	19.90		$	2,483
Canceled/forfeited/expired	(257,277)	$	85.51		$	—
Outstanding at December 31, 2024	3,526,556	$	53.65	4.32	$	16,147
Vested and expected to vest at December 31, 2024	3,525,815	$	53.65	4.32	$	16,147
Exercisable at December 31, 2024	3,496,909	$	53.44	4.30	$	16,147

Schedule of Restricted Stock Units

The following table summarizes RSU activities, which includes performance-based RSUs, for the Company’s stock incentive plans:


	Total RSUs	Weighted-Average Grant Date Fair Value		Aggregate Intrinsic Value (in thousands)
Unvested awards outstanding at December 31, 2021	610,731	$	95.08	$	91,927
Granted	1,542,859	$	67.09
Vested	(202,215)	$	91.99
Canceled/forfeited	(117,543)	$	84.20
Unvested awards outstanding at December 31, 2022	1,833,832	$	72.57	$	82,431
Granted	2,359,907	$	28.13
Vested	(735,155)	$	73.17
Canceled/forfeited	(282,425)	$	59.17
Unvested awards outstanding at December 31, 2023	3,176,159	$	40.61	$	93,951
Granted	2,332,553	$	44.52
Vested	(1,475,409)	$	42.76
Canceled/forfeited	(294,533)	$	41.05
Unvested awards outstanding at December 31, 2024	3,738,770	$	42.17	$	134,670
Awards expected to vest at December 31, 2024	3,571,843	$	42.35	$	128,658

Schedule of Compensation Cost Included in Consolidated Statement of Operations

The following table summarizes the allocation of stock-based compensation expense included in the consolidated statements of operations for all stock-based compensation arrangements (in thousands):


	Year Ended December 31,
		2024		2023		2022
Cost of sales		$	7,361	$	6,212	$	7,685
Selling, general and administrative		62,794		56,303		57,196
Research and development		31,228		25,561		20,037
Total stock-based compensation expense		$	101,383	$	88,076	$	84,918

Schedule of Share-Based Payment Award, Employee Stock Purchase Plan, Valuation Assumptions

The assumptions used in the Black-Scholes option pricing model for the ESPP were as follows:


					ESPP
	Year Ended December 31,
		2024			2023			2022
Weighted average grant date fair value (per share)		$	17.01		$	10.35		$	21.89
Risk-free interest rate		4.7		%	4.9		%	3.4		%
Dividend yield		0.0		%	0.0		%	0.0		%
Expected volatility		67.5		%	63.9		%	56.9		%
Expected term (in years)		1.3			1.3			1.3

Debt - Additional Information (Details)				1 Months Ended		12 Months Ended
Debt - Additional Information (Details)	Mar. 08, 2024 USD ($) trading_day $ / shares	Mar. 05, 2024 USD ($) $ / shares	Jul. 21, 2022 USD ($)	Mar. 31, 2024 USD ($) $ / shares	May 31, 2020 USD ($) trading_day $ / shares	Dec. 31, 2024 USD ($)	Dec. 31, 2023 USD ($)	Dec. 31, 2022 USD ($)	Oct. 31, 2023
Debt Instrument [Line Items]
Proceeds from convertible senior notes						$ 306,850,000	$ 0	$ 0
Repurchased face amount						246,740,000
Loss on extinguishment of debt						1,268,000	0	0
Net proceeds to repurchase of common shares						$ 30,000,000	0	$ 0
Capillary Biomedical
Debt Instrument [Line Items]
Interest rate						5.00%
Long term debt assumed			$ 4,700,000			$ 4,800,000	4,700,000
Convertible Senior Notes Due 2029 \| Convertible Senior Notes
Debt Instrument [Line Items]
Principal amount	$ 316,300,000			$ 316,300,000		316,250,000
Interest rate	1.50%
Net proceeds from issuance of convertible notes	$ 306,800,000
Proceeds from convertible senior notes	246,100,000
Net proceeds to repurchase of common shares	30,000,000
Average cost per share (in dollars per share) \| $ / shares		$ 27.105
Net proceeds to pay for capped call transactions	$ 15,800,000
Debt instrument, convertible, conversion ratio	0.0289361
Conversion price (in dollars per share) \| $ / shares	$ 34.56
Debt instrument, convertible, threshold trading days \| trading_day	20
Debt instrument, convertible, threshold trading days consecutive trading days \| trading_day	30
Redemption price percentage	100.00%
Principal amount						13,400,000
Capped call transactions net cost				$ 15,800,000
Debt instrument, initial cap price per share (in dollars per share) \| $ / shares				$ 42.0128
Convertible Senior Notes Due 2029 \| Convertible Senior Notes \| Conversion Instance, 130%
Debt Instrument [Line Items]
Debt instrument, convertible, threshold trading days \| trading_day	20
Debt instrument, convertible, threshold trading days consecutive trading days \| trading_day	30
Convertible Senior Notes Due 2029 \| Convertible Senior Notes \| Conversion Instance, 98%
Debt Instrument [Line Items]
Debt instrument, convertible, threshold trading days \| trading_day	5
Debt instrument, convertible, threshold trading days consecutive trading days \| trading_day	10
Convertible Senior Notes Due 2029 \| Convertible Senior Notes \| Minimum
Debt Instrument [Line Items]
Debt instrument, convertible, threshold percentage of stock price trigger	130.00%
Convertible Senior Notes Due 2029 \| Convertible Senior Notes \| Minimum \| Conversion Instance, 130%
Debt Instrument [Line Items]
Debt instrument, convertible, threshold percentage of stock price trigger	130.00%
Convertible Senior Notes Due 2029 \| Convertible Senior Notes \| Minimum \| Conversion Instance, 98%
Debt Instrument [Line Items]
Debt instrument, convertible, threshold percentage of stock price trigger	98.00%
Convertible Senior Notes Due 2025 \| Convertible Senior Notes
Debt Instrument [Line Items]
Principal amount					$ 287,500,000	40,760,000	287,500,000
Interest rate					1.50%				1.50%
Net proceeds from issuance of convertible notes					$ 244,600,000
Repurchased face amount				$ 246,700,000		246,700,000
Interest expense	$ 1,300,000
Loss on extinguishment of debt						1,300,000
Debt instrument, convertible, conversion ratio					0.0088836
Conversion price (in dollars per share) \| $ / shares					$ 112.57
Debt instrument, convertible, threshold trading days \| trading_day					20
Debt instrument, convertible, threshold trading days consecutive trading days \| trading_day					30
Redemption price percentage					100.00%
Principal amount						$ 0	0
Additional interest accrual rate					0.0050
Additional interest							$ 3,300,000
Capped call transactions net cost					$ 34,100,000
Debt instrument, initial cap price per share (in dollars per share) \| $ / shares					$ 173.18
Proceeds from capped call termination		$ 200,000
Convertible Senior Notes Due 2025 \| Convertible Senior Notes \| Minimum
Debt Instrument [Line Items]
Debt instrument, convertible, threshold percentage of stock price trigger					130.00%

Composition of Certain Financial Statement Items - Intangible Assets Subject to Amortization (Details) - USD ($) $ in Thousands	Dec. 31, 2024	Dec. 31, 2023
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Intangible assets, gross amount	$ 12,502	$ 12,502
Accumulated amortization	(11,577)	(9,726)
Intangible assets, net	$ 925	$ 2,776
Weighted average remaining amortization period (in months)	6 months	18 months

Leases (Tables)

12 Months Ended

Dec. 31, 2024

Leases [Abstract]

Schedule of Lease Cost

The Company’s lease costs recorded in the consolidated statements of operations were as follows (in thousands):


	Year Ended December 31,
		2024		2023		2022
Operating lease cost		$	14,276	$	15,971	$	18,432
Short-term lease cost		87		108		142
Loss on lease termination and right-of-use asset impairment charges		—		11,224		5,699
Total lease cost		$	14,363	$	27,303	$	24,273

The weighted-average remaining lease term and weighted-average discount rate for operating leases were as follows:


	December 31, 2024		December 31, 2023
Weighted-average remaining lease term (in years)	9.2		10.2
Weighted-average discount rate used to determine operating lease liabilities	5.3	%	5.4	%

Cash amounts paid included in the measurement of lease liabilities, representing operating cash flows, were as follows:


	Year Ended December 31,
	2024		2023		2022
Operating lease payments	17,941		13,864		11,960
Operating lease termination payments	—		—		4,769
Total cash payments	$	17,941	$	13,864	$	16,729

Schedule of Future Minimum Payments Under Non-cancellable Operating Leases

Maturities of operating lease liabilities at December 31, 2024 were as follows (in thousands):


Years Ending December 31,
2025	$	18,208
2026	18,102
2027	18,406
2028	14,890
2029	13,413
Thereafter	76,891
Total undiscounted lease payments	159,910
Less: amount representing interest	(35,281)
Present value of operating lease liabilities	124,629
Less: current portion of operating lease liabilities	(18,208)
Operating lease liabilities - long-term	$	106,421

Income Taxes - Schedule of Deferred Tax Assets and Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2024	Dec. 31, 2023
Deferred tax assets:
Net operating loss (NOL) carryforwards	$ 40,536	$ 54,802
Research and development tax credits carryforwards	32,298	27,516
Capitalized research and development expenses	74,974	52,875
Accrued compensation	38,053	32,097
Lease liabilities	29,165	31,037
Warranty reserve	12,222	8,786
Other	8,610	11,992
Total deferred tax assets	235,858	219,105
Deferred tax liabilities:
Operating lease right-of-use assets	(19,792)	(20,869)
Fixed assets	(5,485)	(6,916)
Other	(218)	(656)
Total deferred tax liabilities	(25,495)	(28,441)
Less valuation allowance	(210,363)	(190,664)
Net deferred tax assets	$ 0	$ 0

Organization and Basis of Presentation	12 Months Ended
Organization and Basis of Presentation	Dec. 31, 2024
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Organization and Basis of Presentation	Organization and Basis of Presentation The Company Tandem Diabetes Care, a global insulin delivery and diabetes technology company, manufactures and sells advanced automated insulin delivery systems that reduce the burden of diabetes management, while creating new possibilities for patients, their loved ones and healthcare providers. Tandem Diabetes Care, Inc. is incorporated in the state of Delaware. Unless the context requires otherwise, the terms the “Company” or “Tandem” refer to Tandem Diabetes Care, Inc., together with its wholly-owned subsidiaries. The Company manufactures, sells, and supports insulin pump products that are designed to address the evolving needs and preferences of differentiated segments of the insulin-dependent diabetes market. The Company recently expanded its insulin pump portfolio, which now includes both the t:slim X2 and the Tandem Mobi. Both pumps feature Control-IQ technology, which is the Company’s advanced algorithm for managing insulin delivery, using information received from integrated continuous glucose monitoring (CGM) sensors. New software for the insulin pumps may be updated remotely by the individual users as new advancements become available and are compatible with other complementary digital health offerings, such as the mobile application and cloud-based diabetes management applications. The Company’s insulin pump systems products are generally considered durable medical equipment and have an expected lifespan of at least four years. In addition to insulin pumps, the Company sells single-use components that are used together with the pumps and are replaced every few days, including cartridges for storing and delivering insulin, and infusion sets that connect the insulin pump to a user’s body. Basis of Presentation and Principles of Consolidation The Company has prepared the accompanying consolidated financial statements in accordance with accounting principles generally accepted in the United States of America, or U.S. GAAP. The statements include the accounts of Tandem Diabetes Care, Inc. and its wholly-owned subsidiaries. All significant intercompany balances and transactions have been eliminated in consolidation. The functional currency of the Company’s foreign subsidiaries is their respective local currency. The Company translates the financial statements of its foreign subsidiaries into U.S. dollars using period-end exchange rates for assets and liabilities and average exchange rates for each period for revenue, costs and expenses. Translation related adjustments are included in other comprehensive income (loss), and in accumulated other comprehensive income (loss) in the stockholders’ equity section of the Company’s consolidated balance sheets. Foreign exchange gains or losses resulting from balances denominated in a currency other than the functional currency are recognized in interest income and other, net in the Company’s consolidated statements of operations.

CONSOLIDATED BALANCE SHEETS (Parenthetical) - $ / shares	Dec. 31, 2024	Dec. 31, 2023
Statement of Financial Position [Abstract]
Common stock, par value (in dollars per share)	$ 0.001	$ 0.001
Common stock, shares authorized (in shares)	200,000,000	200,000,000
Common stock, shares issued (in shares)	66,264,000	65,552,000
Common stock, shares outstanding (in shares)	66,264,000	65,552,000

Summary of Significant Accounting Policies - Customers Accounted for 10% or More (Detail) - Customer Concentration Risk	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Total Sales \| Distributor A
Concentration Risk [Line Items]
Customers accounted for 10% or more	11.20%	12.20%	11.60%
Total Sales \| Distributor D
Concentration Risk [Line Items]
Customers accounted for 10% or more	11.50%	10.80%	14.40%
Accounts Receivable, net \| Distributor A
Concentration Risk [Line Items]
Customers accounted for 10% or more	11.10%	10.00%
Accounts Receivable, net \| Distributor B
Concentration Risk [Line Items]
Customers accounted for 10% or more		10.50%
Accounts Receivable, net \| Distributor C
Concentration Risk [Line Items]
Customers accounted for 10% or more	11.80%	10.60%
Accounts Receivable, net \| Distributor D
Concentration Risk [Line Items]
Customers accounted for 10% or more	11.20%	11.50%

Organization and Basis of Presentation (Details)	12 Months Ended
Organization and Basis of Presentation (Details)	Dec. 31, 2024
Insulin Pump \| Minimum
Organization And Basis Of Presentation [Line Items]
Expected life span term	4 years

Composition of Certain Financial Statement Items - Inventory (Details) - USD ($) $ in Thousands	Dec. 31, 2024	Dec. 31, 2023
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Raw materials	$ 32,602	$ 42,783
Work-in-process	33,517	44,026
Finished goods	83,493	71,128
Total inventories	$ 149,612	$ 157,937

Business Segment and Geographic Information (Tables)

12 Months Ended

Dec. 31, 2024

Segment Reporting [Abstract]

Schedule of Disaggregation of Revenue

The table below sets forth revenues for the Company’s two primary geographical markets, based on the geographic location to which its products are shipped (in thousands):


	Year Ended December 31,
		2024		2023		2022
United States		$	672,685	$	554,878	$	588,765
Outside the United States		267,518		192,840		212,452
Total Sales		$	940,203	$	747,718	$	801,217

During the years ended December 31, 2024, 2023 and 2022, sales by product were as follows (in thousands):


	Year Ended December 31,
		2024		2023		2022
Pump		$	434,169	$	365,842	$	431,907



Supplies and other		475,785		406,983		372,859
Net revenue recognized (deferred) for Tandem Choice program		30,249		(25,107)		(3,549)
Total Sales		940,203		747,718		801,217

Income Taxes - Income Tax Expense (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Income Tax Disclosure [Abstract]
Income tax benefit at federal statutory rate	$ (19,293)	$ (46,253)	$ (19,499)
State income tax, net of federal benefit	(1,444)	(1,313)	(926)
Convertible debt leg-out	1,658	0	0
Warrants revaluation	0	0	(31)
Research and development credits	(7,865)	(6,283)	(6,263)
Section 382 limitation	0	(5)	0
Stock-based compensation	5,772	14,904	2,282
Officers' compensation	1,043	1,547	2,931
Recognition of acquired deferred tax assets	0	(5,048)	0
Acquired IPR&D expenses	0	14,938	6,518
Cross-border tax impacts	(1,422)	(307)	31
Foreign rate differential	2,075	7	37
Other	1,159	1,374	894
Change in valuation allowance	22,472	28,796	15,768
Income tax expense	$ 4,155	$ 2,357	$ 1,742

Fourth Quarter Financial Data (Unaudited) (Tables)

12 Months Ended

Dec. 31, 2024

Quarterly Financial Information Disclosure [Abstract]

Schedule of Quarterly Financial Information


	For the Quarter Ended
	December 31, 2024		December 31, 2023
Sales(1)	$	282,648	$	196,796
Gross profit(1)(2)	$	157,455	$	93,295
Operating expenses	$	158,036	$	128,355
Operating loss	$	(581)	$	(35,060)
Net income (loss)	$	755	$	(30,002)
Basic net income (loss) per share	$	0.01	$	(0.46)
Weighted average shares used to compute basic net income (loss) per share	65,939		65,369
Diluted net income (loss) per share	$	0.01	$	(0.46)
Weighted average shares used to compute diluted net income (loss) per share	66,157		65,369

(2) For the quarter ended December 31, 2024, the Company recognized charges to cost of sales of $0.6 million for Tandem Choice fulfillments in 2024, with no corresponding charge in 2023.

The numerator and denominator of the basic and diluted net income per share computations are calculated as follows for the three months ended December 31, 2024 (in thousands).


	For the Quarter Ended
	December 31, 2024


Net income - basic and diluted	$	754

Weighted average shares outstanding - basic	65,939
Dilutive common share equivalents:
Options to purchase common stock	112

Warrants to purchase common stock	59
Awards to be granted under the ESPP	47

Weighted average shares outstanding - diluted	66,157

Fair Value Measurements - Financial Assets and Liabilities Measured at Fair Value on Recurring Basis (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt securities, available for sale	$ 369,095	$ 409,044
Maximum
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash equivalents maturity term	3 months	3 months
United States Treasury securities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt securities, available for sale	$ 103,702	$ 115,004
Commercial paper
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt securities, available for sale	23,264	72,511
Corporate debt securities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt securities, available for sale	105,836	39,375
Foreign government bonds
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt securities, available for sale	3,013
Fair Value, Measurements, Recurring
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total assets	425,329	457,077
Fair Value, Measurements, Recurring \| Level 1
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total assets	159,936	163,037
Fair Value, Measurements, Recurring \| Level 2
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total assets	265,393	294,040
Fair Value, Measurements, Recurring \| Level 3
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total assets	0	0
Fair Value, Measurements, Recurring \| Cash equivalents
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash equivalents	56,234	48,033
Fair Value, Measurements, Recurring \| Cash equivalents \| Level 1
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash equivalents	56,234	48,033
Fair Value, Measurements, Recurring \| Cash equivalents \| Level 2
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash equivalents	0	0
Fair Value, Measurements, Recurring \| Cash equivalents \| Level 3
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash equivalents	0	0
Fair Value, Measurements, Recurring \| United States Government-sponsored enterprises
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt securities, available for sale	133,280	182,154
Fair Value, Measurements, Recurring \| United States Government-sponsored enterprises \| Level 1
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt securities, available for sale	0	0
Fair Value, Measurements, Recurring \| United States Government-sponsored enterprises \| Level 2
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt securities, available for sale	133,280	182,154
Fair Value, Measurements, Recurring \| United States Government-sponsored enterprises \| Level 3
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt securities, available for sale	0	0
Fair Value, Measurements, Recurring \| United States Treasury securities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt securities, available for sale	103,702	115,004
Fair Value, Measurements, Recurring \| United States Treasury securities \| Level 1
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt securities, available for sale	103,702	115,004
Fair Value, Measurements, Recurring \| United States Treasury securities \| Level 2
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt securities, available for sale	0	0
Fair Value, Measurements, Recurring \| United States Treasury securities \| Level 3
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt securities, available for sale	0	0
Fair Value, Measurements, Recurring \| Commercial paper
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash equivalents	23,264	72,511
Fair Value, Measurements, Recurring \| Commercial paper \| Level 1
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash equivalents	0	0
Fair Value, Measurements, Recurring \| Commercial paper \| Level 2
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash equivalents	23,264	72,511
Fair Value, Measurements, Recurring \| Commercial paper \| Level 3
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash equivalents	0	0
Fair Value, Measurements, Recurring \| Corporate debt securities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt securities, available for sale	105,836	39,375
Fair Value, Measurements, Recurring \| Corporate debt securities \| Level 1
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt securities, available for sale	0	0
Fair Value, Measurements, Recurring \| Corporate debt securities \| Level 2
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt securities, available for sale	105,836	39,375
Fair Value, Measurements, Recurring \| Corporate debt securities \| Level 3
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt securities, available for sale	0	$ 0
Fair Value, Measurements, Recurring \| Foreign government bonds
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt securities, available for sale	3,013
Fair Value, Measurements, Recurring \| Foreign government bonds \| Level 1
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt securities, available for sale	0
Fair Value, Measurements, Recurring \| Foreign government bonds \| Level 2
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt securities, available for sale	3,013
Fair Value, Measurements, Recurring \| Foreign government bonds \| Level 3
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt securities, available for sale	$ 0