Tandem Diabetes Care (TNDM) 10-Q 4 May 22 2022 Q1 Quarterly report Financial data

Cover Page

Cover Page - shares	3 Months Ended
	Mar. 31, 2022	Apr. 29, 2022
Cover [Abstract]
Document Type	10-Q
Document Quarterly Report	true
Document Period End Date	Mar. 31, 2022
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	11075 Roselle Street
Entity Address, City or Town	San Diego,
Entity Address, State or Province	CA
Entity Address, Postal Zip Code	92121
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 Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Large Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Shell Company	false
Entity Common Stock, Shares Outstanding (in shares)		63,962,732
Amendment Flag	false
Document Fiscal Year Focus	2022
Document Fiscal Period Focus	Q1
Entity Central Index Key	0001438133
Current Fiscal Year End Date	--12-31

CONDENSED CONSOLIDATED BALANCE

CONDENSED CONSOLIDATED BALANCE SHEETS - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021
Current assets:
Cash and cash equivalents	$ 93,681	$ 71,181
Short-term investments	541,710	552,630
Accounts receivable, net	94,133	110,725
Inventories	79,987	68,551
Prepaid and other current assets	8,953	8,433
Total current assets	818,464	811,520
Property and equipment, net	49,987	50,386
Operating lease right-of-use assets	131,058	27,503
Other long-term assets	15,768	15,728
Total assets	1,015,277	905,137
Current liabilities:
Accounts payable	45,341	28,032
Accrued expenses	6,362	9,419
Employee-related liabilities	38,258	51,556
Operating lease liabilities	8,080	9,279
Deferred revenue	10,881	10,182
Other current liabilities	22,893	23,388
Total current liabilities	131,815	131,856
Convertible senior notes, net - long-term	281,905	281,467
Operating lease liabilities - long-term	129,195	23,922
Deferred revenue - long-term	17,531	16,940
Other long-term liabilities	17,449	17,840
Total liabilities	577,895	472,025
Commitments and contingencies (Note 12)	0	0
Stockholders’ equity:
Common stock, $0.001 par value; 200,000 shares authorized, 63,941 and 63,833 shares issued and outstanding at March 31, 2022 and December 31, 2021, respectively.	64	64
Additional paid-in capital	1,089,689	1,068,259
Accumulated other comprehensive loss	(3,061)	(616)
Accumulated deficit	(649,310)	(634,595)
Total stockholders’ equity	437,382	433,112
Total liabilities and stockholders’ equity	$ 1,015,277	$ 905,137

CONDENSED CONSOLIDATED BALANC_2

CONDENSED CONSOLIDATED BALANCE SHEETS (Parenthetical) - $ / shares	Mar. 31, 2022	Dec. 31, 2021
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)	63,941,000	63,833,000
Common stock, shares outstanding (in shares)	63,941,000	63,833,000

CONDENSED CONSOLIDATED STATEMEN

CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS AND COMPREHENSIVE LOSS - USD ($) shares in Thousands, $ in Thousands	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Income Statement [Abstract]
Sales	$ 175,907	$ 141,037
Cost of sales	84,814	67,750
Gross profit	91,093	73,287
Operating expenses:
Selling, general and administrative	73,271	58,563
Research and development	33,160	17,961
Total operating expenses	106,431	76,524
Operating loss	(15,338)	(3,237)
Other income (expense), net:
Interest income and other, net	381	272
Interest expense	(1,516)	(1,506)
Change in fair value of common stock warrants	34	(690)
Total other expense, net	(1,101)	(1,924)
Loss before income taxes	(16,439)	(5,161)
Income tax benefit	(1,724)	(117)
Net loss	(14,715)	(5,044)
Other comprehensive loss:
Unrealized loss on short-term investments	(2,517)	(38)
Foreign currency translation gain (loss)	72	(76)
Comprehensive loss	$ (17,160)	$ (5,158)
Net loss per share, basic (in dollars per share)	$ (0.23)	$ (0.08)
Net loss per share, diluted (in dollars per share)	$ (0.23)	$ (0.08)
Weighted average shares used to compute basic net loss per share (in shares)	63,880	62,448
Weighted average shares used to compute diluted net loss per share (in shares)	63,880	62,448

CONDENSED CONSOLIDATED STATEM_2

CONDENSED CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY (Unaudited) - USD ($) shares in Thousands, $ in Thousands	Total	Cumulative Effect, Period of Adoption, Adjustment	[1]	Common Stock	Additional Paid-in Capital	Additional Paid-in CapitalCumulative Effect, Period of Adoption, Adjustment	[1]	Accumulated Other Comprehensive Income (Loss)	Accumulated Deficit	Accumulated DeficitCumulative Effect, Period of Adoption, Adjustment	[1]
Beginning balance (in shares) at Dec. 31, 2020				62,335
Beginning balance at Dec. 31, 2020	$ 366,305	$ (76,754)		$ 62	$ 1,025,233	$ (85,803)		$ 220	$ (659,210)	$ 9,049
Increase (Decrease) in Stockholders' Equity
Exercise of stock options (in shares)				111
Exercise of stock options	3,136			$ 1	3,135
Exercise of common stock warrants (in shares)				125
Exercise of common stock warrants	437				437
Fair value of common stock warrants at time of exercise	12,434				12,434
Stock-based compensation expense	13,014				13,014
Unrealized loss on short-term investments	(38)							(38)
Foreign currency translation adjustments	(76)							(76)
Net loss	(5,044)								(5,044)
Ending balance (in shares) at Mar. 31, 2021				62,571
Ending Balance at Mar. 31, 2021	313,414			$ 63	968,450			106	(655,205)
Beginning balance (in shares) at Dec. 31, 2021				63,833
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)				101
Exercise of stock options	3,782			$ 0	3,782
Vesting of restricted stock units, net of shares withheld for taxes (in shares)				5
Vesting of restricted stock units, net of shares withheld for taxes	(299)				(299)
Exercise of common stock warrants (in shares)				2
Exercise of common stock warrants	16				16
Stock-based compensation expense	17,931				17,931
Unrealized loss on short-term investments	(2,517)							(2,517)
Foreign currency translation adjustments	72							72
Net loss	(14,715)								(14,715)
Ending balance (in shares) at Mar. 31, 2022				63,941
Ending Balance at Mar. 31, 2022	$ 437,382			$ 64	$ 1,089,689			$ (3,061)	$ (649,310)
[1]	The Company adopted ASU No. 2020-06, Accounting for Convertible Instruments and Contracts in an Entity’s Own Equity effective January 1, 2021 (see Note 2, “Summary of Significant Accounting Policies”).

CONSOLIDATED STATEMENTS OF CASH

CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Operating Activities
Net loss	$ (14,715)	$ (5,044)
Adjustments to reconcile net loss to net cash provided by operating activities:
Depreciation and amortization expense	3,628	3,485
Amortization of debt issuance costs	438	428
Provision for expected credit losses	846	143
Provision for inventory obsolescence	346	64
Change in fair value of common stock warrants	(34)	690
Amortization of premium on short-term investments	562	209
Stock-based compensation expense	18,110	12,947
Other	468	(73)
Changes in operating assets and liabilities:
Accounts receivable, net	15,729	8,389
Inventories	(11,963)	(3,084)
Prepaid and other current assets	741	(1,412)
Other long-term assets	(582)	(17)
Accounts payable & accrued expenses	13,732	10,815
Employee-related liabilities	(13,299)	(1,448)
Deferred revenue	1,290	1,871
Operating leases and other current liabilities	(1,106)	1,094
Other long-term liabilities	(391)	(372)
Net cash provided by operating activities	13,800	28,685
Investing Activities
Purchases of short-term investments	(110,719)	(154,300)
Proceeds from maturities of short-term investments	111,559	140,200
Proceeds from sales of short-term investments	7,000	11,530
Purchases of property and equipment	(2,643)	(3,524)
Net cash provided by (used in) investing activities	5,197	(6,094)
Financing Activities
Proceeds from issuance of common stock under Company stock plans, net	3,484	3,135
Proceeds from exercise of common stock warrants	16	438
Net cash provided by financing activities	3,500	3,573
Effect of foreign exchange rate changes on cash	3	14
Net increase in cash and cash equivalents	22,500	26,178
Cash and cash equivalents at beginning of period	71,181	94,613
Cash and cash equivalents at end of period	93,681	120,791
Supplemental disclosures of cash flow information
Income taxes paid	170	197
Supplemental schedule of non-cash investing and financing activities
Right-of-use assets obtained in exchange for operating lease obligations	107,478	15,087
Purchase of property and equipment included in accounts payable	1,553	924
Intangible costs in accounts payable and other long-term liabilities	$ 1,029	$ 2,244

Organization and Basis of Prese

Organization and Basis of Presentation	3 Months Ended
	Mar. 31, 2022
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Organization and Basis of Presentation	Organization and Basis of Presentation The Company Tandem Diabetes Care, Inc. is a medical device company focused on the design, development and commercialization of technology solutions for people living with diabetes. 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 in the U.S., Canada and the Netherlands. 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’s manufacturing, sales and support activities principally focus on the t:slim X2 Insulin Delivery System (t:slim X2), the Company’s flagship pump platform which is capable of remote software updates and is designed to display continuous glucose monitoring (CGM) sensor information directly on the pump home screen. The Company’s insulin pump products are compatible with other complementary digital health offerings, such as the t:connect cloud-based diabetes management application (t:connect) and the Tandem Device Updater, a Mac and PC-compatible tool which offers and supports updates of the Company’s insulin pump software from a personal computer. The Company’s insulin pump 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 disposable products 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, as well as other accessories for enhanced usability. Basis of Presentation and Principles of Consolidation The Company has prepared the accompanying unaudited condensed consolidated financial statements in accordance with accounting principles generally accepted in the United States of America (U.S. GAAP) for interim financial information and pursuant to the instructions to Form 10-Q and Article 10 of Regulation S-X. Accordingly, they do not include all of the information and disclosures required by U.S. GAAP for complete financial statements. In the opinion of management, all adjustments which are of a normal and recurring nature, considered necessary for a fair presentation of the financial information contained herein, have been included. Interim financial results are not necessarily indicative of results anticipated for the full year or any other period(s). These unaudited condensed consolidated financial statements should be read in conjunction with the Company’s audited consolidated financial statements and accompanying notes included in the Company’s Annual Report on Form 10-K for the year ended December 31, 2021 (Annual Report), from which the balance sheet information herein was derived. The condensed consolidated financial 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 subsidiary is the local currency. The Company translates the financial statements of its foreign subsidiary 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 loss, and in accumulated other comprehensive income in the stockholders’ equity section of the Company’s condensed 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 condensed consolidated statements of operations. Reclassifications Starting with the first quarter of 2022, the Company included the liability related to common stock warrants (see Note 5, “Fair Value Measurements”) as a component of other current liabilities on the Company’s condensed consolidated balance sheet. In addition, deferred revenue long-term, which was previously reported as a component of other long-term liabilities, is now separately reported on the condensed consolidated balance sheet. The corresponding balances at December 31, 2021, have been reclassified to conform to the current year presentation.

Summary of Significant Accounti

Summary of Significant Accounting Policies	3 Months Ended
	Mar. 31, 2022
Accounting Policies [Abstract]
Summary of Significant Accounting Policies	Summary of Significant Accounting PoliciesThere have been no material changes to the Company’s significant accounting policies during the three months ended March 31, 2022, as compared to those disclosed in the Company’s 2021 Annual Report. 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. 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 risk, review of outstanding invoices, forecasts about the future, and various assumptions and estimates that are believed to be reasonable under the circumstances, which included the Company’s estimates of credit risks as a result of the coronavirus pandemic (COVID-19 global pandemic). 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. 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. The carrying value and estimated fair value of certain of the Company’s common stock warrants was determined using the Black-Scholes pricing model as of March 31, 2022 and December 31, 2021 (see Note 5, “Fair Value Measurements”). Operating Lease Right-of-Use Assets and Liabilities 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 (the Commencement Date) based on the present value of lease payments over the lease term. For lease agreements entered into or reassessed after the adoption of ASC 842 Leases , the Company combines lease and non-lease components. 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. Cost Basis Equity Investment The Company made an $8.1 million equity investment in a private company in 2021, which represented less than 5% of the outstanding equity of that company. The investment is recorded using the cost minus impairment adjusted for changes in observable prices and is included as a component of other long-term assets on the consolidated balance sheets. The Company monitors this investment to evaluate whether any increase or decline in its value has occurred, based on the implied value of recent company financings, public market prices of comparable companies and general market conditions. 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. The Company reviews its finite-lived intangible assets for impairment whenever events or changes in circumstances indicate that the carrying amount of an asset may not be recoverable. The Company did not recognize any impairment losses during the three months ended March 31, 2022 and 2021. In 2020, the Company acquired Sugarmate, Inc. (Sugarmate), the developer of a mobile app designed to help people visualize diabetes therapy data in innovative ways. The Sugarmate acquisition was accounted for as an acquisition of assets. Substantially all of the fair value was concentrated in a single identifiable asset, a technology-based intangible asset. The purchased intangible asset is amortized on a straight-line basis over an estimated useful life of five years. Revenue Recognition Revenue is generated primarily from sales of insulin pumps, disposable 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 returns. Revenue Recognition for Arrangements with Multiple Performance Obligations The Company considers the individual deliverables in its product offering as 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 t:connect and the Tandem Device Updater, 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. 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. Additionally, the Company offers a six-month warranty on disposable 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 estimated primarily based on the current expected product replacement cost and expected replacement rates utilizing historical experience. Insulin pumps returned to the Company may be refurbished and redeployed. Experience has shown that initial data for any given pump version may be insufficient; therefore, the Company’s process relies on long-term historical averages until sufficient data are available. As actual experience becomes available, the Company uses the data to update the historical averages. The Company may make further adjustments to the warranty reserve when deemed appropriate, giving additional consideration to the length of time each pump version has been in the field and revised future expectations of performance based on new features and capabilities that may become available through Tandem Device Updater. The following table provides a reconciliation of the changes in product warranty liabilities for the three months ended March 31, 2022 and 2021 (in thousands): Three Months Ended March 31, 2022 2021 Balance at beginning of the period $ 30,401 $ 22,075 Provision for warranties issued during the period 7,201 5,896 Settlements made during the period (6,021) (4,256) Decrease in warranty estimates (1,137) (546) Balance at end of the period $ 30,444 $ 23,169 As of March 31, 2022 and December 31, 2021, total product warranty reserves were included in the following consolidated balance sheet accounts (in thousands): March 31, 2022 December 31, 2021 Other current liabilities $ 13,509 $ 13,076 Other long-term liabilities 16,935 17,325 Total warranty reserve $ 30,444 $ 30,401 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 Amended and Restated 2013 Stock Incentive Plan (2013 Plan) and the fair value of the employees’ purchase rights under the Company’s 2013 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 2013 Plan 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 issued under the 2013 Plan that vest based upon the Company’s actual performance relative to predefined performance metrics is 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, subject to the awardee’s continuing service through the measurement date. 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. 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 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 common stock warrants that are recorded as a liability in the accompanying condensed consolidated balance sheets, the calculation of diluted loss per share requires that, to the extent the average market price of the underlying shares for the reporting period exceeds the exercise price of the warrants and the presumed exercise of the warrants is dilutive to loss per share for the period, an adjustment is made to net loss used in the calculation to remove the change in fair value of the warrants from the numerator for the period. Likewise, an adjustment to the denominator is required to reflect the related dilutive shares, if any, under the treasury stock method. For the three months ended March 31, 2022 and 2021, 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. 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): Three Months Ended 2022 2021 Options to purchase common stock 4,424 5,068 Unvested restricted stock units 630 133 Warrants to purchase common stock 211 379 Awards granted under the ESPP 78 78 Convertible senior notes (if-converted) 2,554 2,554 7,897 8,212 Recent Accounting Pronouncements In June 2020, the FASB issued ASU No. 2020-06, Accounting for Convertible Instruments and Contracts in an Entity’s Own Equity , which is intended to simplify the accounting for convertible instruments. This new guidance eliminated certain models that require separate accounting for embedded conversion features, and eliminated certain of the conditions for equity classification for contracts in an entity’s own equity. Accordingly, a convertible debt instrument will be accounted for as a single liability measured at its amortized cost, as long as no other features require bifurcation and recognition as derivatives. The new guidance could be adopted through either a modified retrospective method of transition or a fully retrospective method of transition. ASU 2020-06 is effective for public business entities for fiscal years beginning after December 15, 2021, including interim periods within those fiscal years. Early adoption is permitted for fiscal years beginning after December 15, 2020, including interim periods within those fiscal years. The Company elected to early adopt the new standard on January 1, 2021 using the modified retrospective method and, accordingly, recorded a net reduction to accumulated deficit of $9.0 million, a decrease to additional paid-in capital of $85.8 million, and an increase to convertible senior notes, net - long-term of $76.8 million to reflect the impact of the accounting change (see Note 7, “Debt”).

Short-Term Investments

Short-Term Investments	3 Months Ended
	Mar. 31, 2022
Investments, Debt and Equity Securities [Abstract]
Short-Term Investments	Short-Term Investments The Company invests in marketable securities primarily consisting of debt instruments of the U.S. Government, U.S. 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 March 31, 2022 and December 31, 2021 (in thousands): At March 31, 2022 Amortized Gross Unrealized Gross Unrealized Estimated Available-for-sale securities: U.S. Treasury securities $ 296,072 $ 1 $ (2,388) $ 293,685 Commercial paper 156,913 — (202) 156,711 Corporate debt securities 51,649 6 (196) 51,459 U.S. Government-sponsored enterprises 37,217 — (362) 36,855 Supranational bonds 3,000 — — 3,000 Total $ 544,851 $ 7 $ (3,148) $ 541,710 At December 31, 2021 Amortized Gross Unrealized Gross Unrealized Estimated Available-for-sale securities: U.S. Treasury securities $ 222,206 $ — $ (482) $ 221,724 Commercial paper 218,391 14 (24) 218,381 Corporate debt securities 58,881 — (45) 58,836 U.S. Government-sponsored enterprises 50,773 1 (88) 50,686 Supranational bonds 3,003 — — 3,003 Total $ 553,254 $ 15 $ (639) $ 552,630 The contractual maturities of available-for-sale debt securities as of March 31, 2022, were as follows (in thousands): Years to Maturity At March 31, 2022 Within One Year One to Two Years Estimated Fair Value U.S. Treasury securities $ 223,643 $ 70,042 $ 293,685 Commercial paper 156,711 — 156,711 Corporate debt securities 43,906 7,553 51,459 U.S. Government-sponsored enterprises 23,612 13,243 36,855 Supranational bonds 3,000 — 3,000 Total $ 450,872 $ 90,838 $ 541,710 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 March 31, 2022 were primarily due to the recent increase in market interest rates. The Company does not intend to sell the available-for-sale debt securities that are in an unrealized loss position, and it is not more likely than not that the Company will be required to sell these debt securities before recovery of their amortized cost bases, which may be at maturity. Based on the credit quality of the available-for-sale debt securities in an unrealized loss position, and the Company’s estimates of future cash flows to be collected from those securities, the Company believes the unrealized losses are not credit losses. Accordingly, the Company did not recognize any impairment losses related to its available-for-sale debt securities at March 31, 2022.

Composition of Certain Financia

Composition of Certain Financial Statement Items	3 Months Ended
	Mar. 31, 2022
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Composition of Certain Financial Statement Items	Composition of Certain Financial Statement Items Accounts Receivable Accounts receivable, net consisted of the following at (in thousands): March 31, 2022 December 31, 2021 Accounts receivable $ 98,477 $ 114,974 Less: allowance for credit losses (4,344) (4,249) Accounts receivable, net $ 94,133 $ 110,725 Allowance for Credit Losses The following table provides a reconciliation of the changes in the allowance for estimated accounts receivable credit losses for the three months ended March 31, 2022 and 2021 (in thousands): Three Months Ended March 31, 2022 2021 Balance at beginning of the period $ 4,249 $ 3,857 Provision for expected credit losses 846 143 Write-offs and adjustments, net of recoveries (751) (441) Balance at end of the period $ 4,344 $ 3,559 Inventories Inventories consisted of the following at (in thousands): March 31, 2022 December 31, 2021 Raw materials $ 28,223 $ 26,911 Work-in-process 18,520 16,612 Finished goods 33,244 25,028 Total inventories $ 79,987 $ 68,551

Fair Value Measurements

Fair Value Measurements	3 Months Ended
	Mar. 31, 2022
Fair Value Disclosures [Abstract]
Fair Value Measurements	Fair Value Measurements Authoritative guidance on fair value measurements defines fair value, and provides a consistent framework for measuring fair value and for disclosures of each major asset and liability category measured at fair value on either a recurring or a nonrecurring basis. Fair value is intended to reflect an assumed exit price, representing the amount that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants. As such, fair value is a market-based measurement that should be determined based on assumptions that market participants would use in pricing an asset or liability. As a basis for considering such assumptions, the authoritative guidance establishes a three-tier fair value hierarchy, which prioritizes the inputs used in measuring fair value as follows: Level 1: Observable inputs such as unadjusted quoted prices in active markets that are accessible at the measurement date for identical, unrestricted assets or liabilities. Level 2: Inputs, other than quoted prices in active markets, that are observable either directly or indirectly for substantially the full term of the asset or liability. Level 3: Unobservable inputs in which there is little or no market data and that are significant to the fair value of the assets or liabilities, which require the reporting entity to develop its own valuation techniques that require input assumptions. The following table presents information about the Company’s financial assets and liabilities measured at fair value on a recurring basis as of March 31, 2022 and December 31, 2021, and indicates the fair value hierarchy of the valuation techniques utilized by the Company to determine such fair value (in thousands): Fair Value Measurements at March 31, 2022 Total Level 1 Level 2 Level 3 Assets Cash equivalents (1) $ 44,905 $ 44,905 $ — $ — U.S. Treasury securities 293,685 293,685 — — Commercial paper 156,711 — 156,711 — Corporate debt securities 51,459 — 51,459 — U.S. Government-sponsored enterprises 36,855 — 36,855 — Supranational bonds 3,000 — 3,000 — Total assets $ 586,615 $ 338,590 $ 248,025 $ — Liabilities Common stock warrants (2) $ 113 $ — $ — $ 113 Total liabilities $ 113 $ — $ — $ 113 Fair Value Measurements at Total Level 1 Level 2 Level 3 Assets Cash equivalents (1) $ 48,286 $ 48,286 $ — $ — U.S. Treasury securities 221,724 221,724 — — Commercial paper 218,381 — 218,381 — Corporate debt securities 58,836 — 58,836 — U.S. Government-sponsored enterprises 50,686 — 50,686 — Supranational bonds 3,003 — 3,003 — Total assets $ 600,916 $ 270,010 $ 330,906 $ — Liabilities Common stock warrants (2) $ 147 $ — $ — $ 147 Total liabilities $ 147 $ — $ — $ 147 (1) Generally, cash equivalents include money market funds and investments with a maturity of three months or less from the date of purchase. (2) Included in other current liabilities on the Company’s condensed consolidated balance sheets. 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. The Company's Level 3 liabilities at March 31, 2022 and December 31, 2021 included the remaining Series A warrants issued by the Company in connection with the public offering of common stock in October 2017. The Series A warrants, which expire in October 2022, provide holders the right to purchase shares of the Company’s common stock at an exercise price of $3.50 per share. As of March 31, 2022 and December 31, 2021, there were Series A warrants outstanding to purchase 1,000 shares of the Company’s common stock (see Note 8, “Stockholders’ Equity”). The Company reassesses the fair value of the outstanding Series A warrants at each reporting date utilizing a Black-Scholes pricing model. Variables used in the pricing model include the closing market price of the Company’s common stock at the balance sheet date, as well as estimated stock price volatility, dividend yield, remaining warrant term and risk-free interest rate. A significant increase (decrease) in any of these inputs in isolation, particularly the market price of the Company’s common stock, would have resulted in a significantly higher (lower) fair value measurement. The assumptions used to estimate the fair values of the outstanding Series A warrants at March 31, 2022 and December 31, 2021 are presented below: Series A Warrants March 31, 2022 December 31, 2021 Risk-free interest rate 1.1 % 0.3 % Expected dividend yield 0.0% 0.0% Expected volatility 44.4 % 39.1 % Expected term (in years) 0.6 0.8 The following table presents a summary of changes in the fair value of the Company’s Level 3 financial liabilities for the three months ended March 31, 2022 and 2021 (in thousands): Three Months Ended March 31, 2022 2021 Balance at beginning of period $ 147 $ 14,261 (Gain) loss recognized from the change in fair value of common stock warrants (34) 690 Common stock warrants exercised during the period — (12,434) Balance at end of period $ 113 $ 2,517

Leases

Leases	3 Months Ended
	Mar. 31, 2022
Leases [Abstract]
Leases	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. Leases with an initial term of 12 months or less (Short-term Lease) are expensed as incurred and are not recorded as right-of-use assets on the Company’s condensed consolidated balance sheets. The Company is required to recognize operating lease right-of-use assets and liabilities, and begin recording lease expense when the Company takes possession of the leased property (the Commencement Date). The Company recognizes lease expense for these leases on a straight-line basis over the lease term. Because the Company’s leases do not provide an implicit interest rate, the Company uses its incremental borrowing rate based on the information available at the lease Commencement Date to determine the operating lease right-of-use assets and liabilities based on the present value of future lease payments over the lease term. The Company used the incremental borrowing rate on January 1, 2019 for operating leases that commenced prior to that date. Certain leases include an option to renew, with renewal terms that can extend the lease term for additional periods. The exercise of lease renewal options is at the Company’s sole discretion. For renewal options that are reasonably certain at the lease Commencement Date of being exercised, the Company includes the renewal option period in the lease term. Vista Sorrento Lease In March 2021, the Company entered into a second amendment (Second Amendment) to its lease agreement for office space located on Vista Sorrento Parkway in San Diego, California (Vista Sorrento Lease) covering 59,013 square feet of general administrative office space (Existing Premises). The Second Amendment expanded the Existing Premises by adding 14,916 square feet of general administrative office space (Expansion Space), and extended the lease term for the Existing Premises through January 2028. The Expansion Space lease Commencement Date occurred in March 2021, and the lease term expires in January 2028. The Company has two options to extend the term of the Vista Sorrento Lease, covering both the Existing Premises and the Expansion Space, with each option providing for an additional period of five years. The Vista Sorrento Lease term was determined assuming the renewal options would not be exercised. The Company recognized right-of-use leased assets and corresponding operating lease liabilities of $15.1 million on the consolidated balance sheet in the first quarter of 2021 related to the Second Amendment. Tech Center Lease In September 2021, the Company entered into a lease agreement for 181,949 square feet of additional general administrative, laboratory, and research and development office space (the Premises) located on High Bluff Drive in San Diego, California (Tech Center Lease). Possession of the Premises is expected to be tendered to the Company by the landlord in two phases, with Phase I consisting of 143,850 rentable square feet, and Phase II consisting of 38,099 rentable square feet. The Company intends to use Phase I of the Tech Center Lease for operations currently occupying 77,458 square feet of leased space, located on Roselle Street in San Diego, California, that is scheduled to expire in May 2023. The initial lease term Phase I Commencement Date occurred in March 2022 when the Company was tendered possession of the Phase I portion of the Premises, and rent payments commence in September 2022 (the Phase I Rent Commencement Date). The Phase II Commencement Date is expected to occur upon the earlier of (i) the date upon which the Company first commences business in the Phase II portion of the Premises, and (ii) May 1, 2025 (the Phase II Rent Commencement Date). The Tech Center 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 Tech Center Lease term was determined assuming the renewal options would not be exercised. The Tech Center Lease also includes a first right of offer with respect to an additional 34,569 rentable square feet of general office space should the space become available. The lease term and associated base rent for the additional space will not be known until the Company is notified that the additional space has become available, and the Company elects to lease the space on terms mutually satisfactory to the Company and the landlord. The initial base rent for the Tech Center Lease is approximately $906,000 per month beginning on the Phase I Rent Commencement Date, and the base rent increases by approximately $255,000 per month on the Phase II Rent Commencement Date. The monthly base rent will increase by 3.0% on each annual anniversary of the respective Rent Commencement Date. In addition to the monthly base rent, the Company is required to pay its proportionate share of certain ongoing operating expenses throughout the duration of the lease. No base rent, other than the proportionate share of operating expenses, will be due for the Phase I portion of the Premises for months two nine two five Supplemental Lease Disclosure Information The Company’s lease costs recorded in the condensed consolidated statements of operations were as follows (in thousands): Three Months Ended March 31, 2022 2021 Operating lease cost $ 3,018 $ 2,006 Short-term lease cost 34 22 Total lease cost $ 3,052 $ 2,028 Maturities of operating lease liabilities at March 31, 2022 were as follows (in thousands): Years Ending December 31, 2022 (remaining) $ 6,387 2023 12,805 2024 17,057 2025 17,475 2026 17,528 Thereafter 120,235 Total undiscounted lease payments 191,487 Less: amount representing interest (54,212) Present value of operating lease liabilities 137,275 Less: current portion of operating lease liabilities (8,080) Operating lease liabilities - long-term $ 129,195 The weighted-average remaining lease term and weighted-average discount rate for operating leases were as follows: March 31, 2022 December 31, 2021 Weighted-average remaining lease term (in years) 11.2 5.0 Weighted-average discount rate used to determine operating lease liabilities 5.4 % 5.6 % Cash paid for amounts included in the measurement of lease liabilities, representing operating cash flows from operating leases, was $3.4 million and $2.3 million for the three months ended March 31, 2022 and 2021, respectively . Leases For Which Accounting Has Not Yet Commenced As of March 31, 2022, the Commencement Date for the High Bluff Lease described below, and Phase II of the Tech Center Lease, had not yet occurred. Accordingly, the condensed consolidated balance sheet at March 31, 2022 does not include operating lease right-of-use assets and operating lease liabilities, and the condensed consolidated statement of operations for the three months ended March 31, 2022 does not include any lease costs, related to the High Bluff Lease and Phase II of the Tech Center Lease. In addition, the above disclosures of the Company’s lease costs, maturities of operating lease liabilities, and the weighted-average remaining lease term and weighted-average discount rate, do not include any amounts related to the High Bluff Lease and Phase II of the Tech Center Lease. High Bluff Lease In May 2021, the Company entered into a lease agreement for approximately 31,372 square feet of general office space located on High Bluff Drive, in San Diego, California (High Bluff Lease). The High Bluff Lease is a direct lease agreement for the same property subject to the High Bluff sublease. The lease term begins in April 2022 following the termination of the High Bluff sublease in March 2022, and is scheduled to expire in March 2024. The Company expects to recognize right-of-use leased assets and corresponding operating lease liabilities of approximately $3.0 million on the consolidated balance sheet on the Commencement Date in the second quarter of 2022. Tech Center Lease - Phase II The Company currently estimates that Phase II Commencement Date will occur in the first quarter of 2025, at which time the Phase II operating lease right-of-use assets and liabilities will be recorded. Future minimum payments for monthly base rent due under Phase II of the Tech Center Lease, are currently estimated to total $34.7 million from 2025 through 2035, subject to a number of factors, including the actual Commencement Date of Phase II. Because the incremental borrowing rate will not be available until the Phase II Commencement Date, we are not yet able to determine the Phase II operating lease right-of-use assets and liabilities.

Debt

Debt	3 Months Ended
	Mar. 31, 2022
Debt Disclosure [Abstract]
Debt	Debt Convertible Senior Notes In May 2020, the Company entered into a purchase agreement with certain counterparties for the sale of an aggregate of $287.5 million principal amount of 1.50% Convertible Senior Notes due 2025 (Notes) in a private offering to qualified institutional buyers pursuant to Rule 144A under the Securities Act of 1933, as amended. 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. The 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 Notes mature on May 1, 2025 unless repurchased, redeemed, or converted in accordance with their terms prior to the maturity date. The 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 Notes, which is equivalent to an initial conversion price of $112.57 (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. The Company expects to settle conversions through a combination settlement, which involves payment in cash equal to the principal portion and delivery of shares of common stock for the excess of the conversion value over the principal portion. The Company may not redeem the Notes prior to May 6, 2023. The Company has the option to redeem for cash all or any portion of the 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 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 Notes to be redeemed, plus accrued and unpaid interest. No sinking fund is provided for the Notes. Holders of the Notes may convert all or a portion of their Notes at their option prior to November 1, 2024, in multiples of $1,000 principal amounts, only under the following circumstances: • if the last reported sale price of the Company’s common stock for at least 20 trading days (whether or not consecutive) during the period of 30 consecutive trading days ending on the last trading day of the immediately preceding calendar quarter is greater than or equal to 130% of the applicable conversion price of the Notes on each such trading day; • during the five business day period after any five consecutive trading day period in which the trading price per $1,000 principal amount of the Notes for each day of that five consecutive trading day 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 Notes on such trading day; • if the Company calls any or all of the Notes for redemption, at any time prior to the close of business on the scheduled trading day immediately preceding the redemption date; or • on the occurrence of specified corporate events. On or after 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. Holders of the 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 Notes may require us to repurchase all or a portion of the 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 Notes on the condensed consolidated balance sheets consisted of the following (in thousands): March 31, 2022 December 31, 2021 Principal amount $ 287,500 $ 287,500 Unamortized debt issuance costs (5,595) (6,033) Net carrying amount $ 281,905 $ 281,467 As of March 31, 2022, the unamortized debt issuance costs of $5.6 million associated with the Notes will be amortized to interest expense, at an effective interest rate of 2.2% over the remaining period of approximately three years. The following table details interest expense recognized related to the Notes for the three months ended March 31, 2022 and 2021 (in thousands): Three Months Ended March 31, 2022 March 31, 2021 Contractual interest expense $ 1,078 $ 1,078 Amortization of debt issuance costs 438 428 Total interest expense $ 1,516 $ 1,506 The Notes will have a dilutive effect to the extent the average market price per share of common stock for a given reporting period exceeds the conversion price of $112.57. As of March 31, 2022, the if-converted value of the Notes exceeded the principal amount by $9.5 million. As of December 31, 2021, the if-converted value of the Notes exceeded the principal amount by $96.9 million. Capped Call Transactions In connection with the issuance of the Notes, the Company entered into Capped Call Transactions in May 2020 with certain counterparties at a net cost of $34.1 million. The Capped Call Transactions are intended to reduce potential dilution to holders of the Company’s common stock beyond the conversion price of $112.57, up to a conversion price of $173.18 on any conversion of the Notes, or to offset any cash payments the Company is required to make in excess of the principal amount of such converted Notes, as the case may be, with such reduction or offset subject to a cap. The cap price of the Capped Call Transactions is initially $173.18 per share of the Company’s common stock, representing a premium of 100% above the last reported sale price of $86.59 per share of the Company’s common stock on May 12, 2020, and is subject to certain adjustments under the terms of the Capped Call Transactions. Conditions that cause adjustments to the initial strike price of the Capped Call Transactions mirror conditions that result in corresponding adjustments for the Notes. For accounting purposes, the Capped Call Transactions are separate transactions, and not part of the terms of the Notes, while they are integrated for federal tax purposes. As these transactions met certain criteria under the applicable accounting guidance, the Capped Call Transactions were recorded in stockholders' equity and were not accounted for as derivatives. The cost of the Capped Call 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.

Stockholders' Equity

Stockholders' Equity	3 Months Ended
	Mar. 31, 2022
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 March 31, 2022 (in thousands): Shares reserved for issuance upon conversion of Convertible Senior Notes 2,554 Shares underlying outstanding warrants 211 Shares underlying outstanding stock options 4,671 Shares underlying unvested restricted stock units 772 Shares authorized for issuance pursuant to awards granted under the ESPP 1,216 Shares authorized for future equity award grants 1,258 Total 10,682 Common Stock Warrants Warrants outstanding to purchase shares of the Company's common stock as of March 31, 2022 were as follows: Issue Date Exercise Price Per Share Warrants Outstanding Expiration Date of Warrants Outstanding October 2017 $3.50 1,000 October 2022 March 2017 $23.50 193,788 March 2027 August 2011 - August 2012 $73.73 16,212 May 2022 - August 2022 211,000 Each warrant allows the holder to purchase one share of the Company's common stock at the exercise price per share of the respective warrant. The Company issued 1,835 and 125,000 shares of its common stock upon the exercise of warrants during the three months ended March 31, 2022 and 2021, respectively. Stock Plans The Company’s Amended and Restated 2013 Stock Incentive Plan (2013 Plan) was originally approved by the Company’s board of directors in October 2013. Under the 2013 Plan, the Company may grant stock options, stock appreciation rights, restricted stock and restricted stock units to individuals who are then employees, officers, directors or consultants of the Company. The ESPP enables eligible employees to purchase shares of the Company’s common stock using their after-tax payroll deductions, subject to certain conditions. 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. There were no shares of common stock purchased under the ESPP during the three months ended March 31, 2022 and 2021. Stock-Based Compensation Common Stock Options Common stock options have an exercise price equal to the closing price of the Company's common stock on the applicable award date, and have a maximum term of ten years. Stock options granted generally vest over a four year period as to 25% of the underlying shares on the first anniversary of the award, with the balance of the options vesting monthly over the following three years. The Company estimates the fair value of stock options using the Black-Scholes option-pricing model on the grant date. The number of common stock options granted and the respective assumptions used in the Black-Scholes option-pricing model were as follows: Three Months Ended March 31, 2022 2021 Stock options granted — 115,400 Weighted average grant date fair value (per share) N/A $ 60.98 Risk-free interest rate N/A 0.9 % Expected dividend yield N/A 0.0 % Expected volatility N/A 75.6 % Expected term (in years) N/A 6.1 Restricted Stock Units Restricted stock units (RSUs) have a grant price equal to the closing price of the Company’s common stock on the award date. RSUs granted prior to March 2022, generally vest over a four year period based only on 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 vest over a three year period based only on service 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. The number of RSUs granted and the respective weighted average grant date fair value were as follows: Three Months Ended 2022 2021 RSUs granted 187,076 3,208 Weighted average grant date fair value (per share) $ 109.97 $ 93.49 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): Three Months Ended March 31, 2022 2021 Cost of sales $ 1,846 $ 1,476 Selling, general & administrative 11,854 9,409 Research and development 4,410 2,062 Total stock-based compensation expense $ 18,110 $ 12,947 The total stock-based compensation capitalized as part of the cost of the Company’s inventories was $0.8 million and $1.0 million at March 31, 2022 and December 31, 2021, respectively.

Employee Benefits

Employee Benefits	3 Months Ended
	Mar. 31, 2022
Retirement Benefits [Abstract]
Employee Benefits	Employee Benefits Employee 401(k) Plan The Company has a defined contribution 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 rehire 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 Company did not provide a matching contribution prior to 2022, but began making a discretionary match in the first quarter of 2022.

Income Taxes

Income Taxes	3 Months Ended
	Mar. 31, 2022
Income Tax Disclosure [Abstract]
Income Taxes	Income Taxes For the three months ended March 31, 2022, the Company recognized an income tax benefit of $1.7 million on a pre-tax loss of $16.4 million, compared to an income tax benefit of $0.1 million on a pre-tax loss of $5.2 million for the three months ended March 31, 2021. The income tax benefit for the three months ended March 31, 2022 and 2021, was primarily attributable to the Company’s pre-tax loss position, offset by state and foreign income tax expense as a result of current taxable income in certain jurisdictions. The Company calculated the provision (benefit) for income taxes for the three months ended March 31, 2022 and 2021, by applying an estimate of the annual effective tax rate for the full year to ordinary income (loss) adjusted by the tax impact of discrete items. The Company continues to maintain a full valuation allowance against its net deferred tax assets as of March 31, 2022, based on the current assessment that it is not more likely than not these future benefits will be realized before expiration.

Business Segment and Geographic

Business Segment and Geographic Information	3 Months Ended
	Mar. 31, 2022
Segment Reporting [Abstract]
Business Segment and Geographic Information	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, disposable insulin cartridges and infusion sets for the storage and delivery of insulin. The Company views its operations and manages its business as one segment and a single reporting unit because key operating decisions and resource allocations are made by the CODM using consolidated financial data. Disaggregation of Revenue 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, including in select European countries, Canada, Australia, New Zealand, Saudi Arabia and South Africa. In the United States and Canada, the Company utilizes a direct sales force. The Company disaggregates its revenue by geography and by major sales channel 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 three months ended March 31, 2022 and 2021, 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). Three Months Ended March 31, 2022 2021 United States $ 131,283 $ 103,339 Outside the United States 44,624 37,698 Total Sales $ 175,907 $ 141,037 Sales to distributors accounted for 65% and 68% of the Company’s total United States sales for the three months ended March 31, 2022 and 2021, respectively. Sales to distributors accounted for 96% and 96% of the Company’s total sales outside the United States for the three months ended March 31, 2022 and 2021, respectively.

Commitments and Contingencies

Commitments and Contingencies	3 Months Ended
	Mar. 31, 2022
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	Commitments and Contingencies Legal and Regulatory Matters In May 2020, the Company was named as a defendant in three California state court class action lawsuits arising from the same data breach. Collectively, these lawsuits seek statutory, compensatory, actual, and punitive damages; equitable relief, including restitution; pre- and post-judgment interest; injunctive relief; and attorney fees, costs, and expenses from the Company. On July 24, 2020, these three pending lawsuits were consolidated into a single case in the Superior Court of the State of California in the County of San Bernardino entitled Joseph Deluna et al v. Tandem Diabetes Care, Inc . The consolidated case alleges violations of the Confidentiality of Medical Information Act (CMIA), California Consumer Privacy Act (CCPA), California’s Unfair Competition Law (UCL), and breach of contract. The Company filed a demurrer seeking dismissal of all claims, which was heard by the Court on October 27, 2020, and which resulted in the following outcome: (i) the demurrer to the CMIA claim was denied; (ii) the demurrer to the CCPA claim was sustained; and (iii) the demurrer to the UCL and contract claims were sustained with leave to amend the pending complaint. A second demurrer was heard by the Court on March 29, 2021 with the following outcome: (i) the demurrer to the CMIA claim was denied; and (ii) the demurrer to the UCL and contract claims was sustained without leave to amend as to three of the named plaintiffs. The plaintiffs filed a motion for class certification on January 7, 2021 to which the Company filed its opposition on April 11, 2022. The Company filed a motion for summary adjudication on the CMIA claim on April 7, 2021, which is still pending. Although the Company continues to vigorously defend against these claims, there is no guarantee that the Company will prevail. The Company presently is unable to determine the ultimate outcome of these lawsuits or determine the amount (or range) of possible losses associated with the lawsuits. In September 2020, the Company was named as a defendant in a lawsuit entitled Buck Walsh, individually and on behalf of others similarly situated v. Tandem Diabetes Care, Inc., which was filed in the Superior Court of the State of California in the County of San Diego. The alleged violations include business and professions code and labor code violations for failure to compensate wages, unpaid meal and rest periods, and failure to reimburse for necessary business-related expenses. The case was brought as a class action and was later amended to also include a representative action under the California Private Attorney General Act, or PAGA. The class of plaintiffs includes hourly paid or non-exempt employees of the Company who were employed from April 6, 2016 through the date of adjudication. The parties recently agreed to resolve all claims in the lawsuit. The settlement of claims covered by the PAGA matter were approved by the Superior Court of the State of California in the County of San Diego on September 21, 2021 and settlement amounts were disbursed in 2021. In October 2021, a settlement of the class action related claims was preliminarily approved by an independent arbitrator mutually acceptable to both parties. The class action is intended to resolve the claims of the individual plaintiff, as well as the remaining members of the class, unless an individual class member submits a timely request for exclusion. The material terms of the settlement are set forth in a binding Memorandum of Agreement dated as of July 1, 2021, which was approved by the independent arbitrator on April 18, 2022. Subsequent to this filing, the Company anticipates receipt of the final settlement amount from the settlement administrator. This lawsuit will be resolved and closed upon disbursement of the settlement amount. 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 the normal course of its business activities, including actions with respect to intellectual property, data privacy, employment, regulatory, product liability and contractual matters. Although the results of legal proceedings, disputes and other claims cannot be predicted with certainty, the Company believes it is not currently a party to any other legal proceeding(s) which, if determined adversely to the Company, would, individually or taken together, have a material adverse effect on the Company’s business, operating results, financial condition or cash flows. 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. Except as set forth above, as of March 31, 2022, there were no 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 merits of the claims raised or the outcome, legal proceedings, regulatory matters, and other disputes and claims may have an adverse impact on the Company because of as a result of defense and settlement costs, diversion of management time and resources, and other factors. Letters of Credit The Company leases general office space, research and development, manufacturing and warehouse facilities, and equipment under noncancelable operating leases for use in its operations (see Note 6, “Leases”). In connection with one of the operating leases, the Company has 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.

Organization and Basis of Pre_2

Organization and Basis of Presentation (Policies)	3 Months Ended
	Mar. 31, 2022
Organization, Consolidation and Presentation of Financial Statements [Abstract]
The Company	The Company Tandem Diabetes Care, Inc. is a medical device company focused on the design, development and commercialization of technology solutions for people living with diabetes. 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 in the U.S., Canada and the Netherlands. 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’s manufacturing, sales and support activities principally focus on the t:slim X2 Insulin Delivery System (t:slim X2), the Company’s flagship pump platform which is capable of remote software updates and is designed to display continuous glucose monitoring (CGM) sensor information directly on the pump home screen. The Company’s insulin pump products are compatible with other complementary digital health offerings, such as the t:connect cloud-based diabetes management application (t:connect) and the Tandem Device Updater, a Mac and PC-compatible tool which offers and supports updates of the Company’s insulin pump software from a personal computer. The Company’s insulin pump 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 disposable products 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, as well as other accessories for enhanced usability.
Basis of Presentation and Principles of Consolidation	Basis of Presentation and Principles of Consolidation The Company has prepared the accompanying unaudited condensed consolidated financial statements in accordance with accounting principles generally accepted in the United States of America (U.S. GAAP) for interim financial information and pursuant to the instructions to Form 10-Q and Article 10 of Regulation S-X. Accordingly, they do not include all of the information and disclosures required by U.S. GAAP for complete financial statements. In the opinion of management, all adjustments which are of a normal and recurring nature, considered necessary for a fair presentation of the financial information contained herein, have been included. Interim financial results are not necessarily indicative of results anticipated for the full year or any other period(s). These unaudited condensed consolidated financial statements should be read in conjunction with the Company’s audited consolidated financial statements and accompanying notes included in the Company’s Annual Report on Form 10-K for the year ended December 31, 2021 (Annual Report), from which the balance sheet information herein was derived. The condensed consolidated financial 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 subsidiary is the local currency. The Company translates the financial statements of its foreign subsidiary 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 loss, and in accumulated other comprehensive income in the stockholders’ equity section of the Company’s condensed 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 condensed consolidated statements of operations.
Reclassifications	ReclassificationsStarting with the first quarter of 2022, the Company included the liability related to common stock warrants (see Note 5, “Fair Value Measurements”) as a component of other current liabilities on the Company’s condensed consolidated balance sheet. In addition, deferred revenue long-term, which was previously reported as a component of other long-term liabilities, is now separately reported on the condensed consolidated balance sheet. The corresponding balances at December 31, 2021, have been reclassified to conform to the current year presentation
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.
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 risk, review of outstanding invoices, forecasts about the future, and various assumptions and estimates that are believed to be reasonable under the circumstances, which included the Company’s estimates of credit risks as a result of the coronavirus pandemic (COVID-19 global pandemic). 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.
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. The carrying value and estimated fair value of certain of the Company’s common stock warrants was determined using the Black-Scholes pricing model as of March 31, 2022 and December 31, 2021 (see Note 5, “Fair Value Measurements”).
Operating Lease Right-of-Use Assets and Liabilities	Operating Lease Right-of-Use Assets and Liabilities 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 (the Commencement Date) based on the present value of lease payments over the lease term. For lease agreements entered into or reassessed after the adoption of ASC 842 Leases , the Company combines lease and non-lease components. 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. The Company reviews its finite-lived intangible assets for impairment whenever events or changes in circumstances indicate that the carrying amount of an asset may not be recoverable. The Company did not recognize any impairment losses during the three months ended March 31, 2022 and 2021. In 2020, the Company acquired Sugarmate, Inc. (Sugarmate), the developer of a mobile app designed to help people visualize diabetes therapy data in innovative ways. The Sugarmate acquisition was accounted for as an acquisition of assets. Substantially all of the fair value was concentrated in a single identifiable asset, a technology-based intangible asset. The purchased intangible asset is amortized on a straight-line basis over an estimated useful life of five years.
Revenue Recognition	Revenue Recognition Revenue is generated primarily from sales of insulin pumps, disposable 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 returns. Revenue Recognition for Arrangements with Multiple Performance Obligations The Company considers the individual deliverables in its product offering as 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 t:connect and the Tandem Device Updater, 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.
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. Additionally, the Company offers a six-month warranty on disposable 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 estimated primarily based on the current expected product replacement cost and expected replacement rates utilizing historical experience. Insulin pumps returned to the Company may be refurbished and redeployed. Experience has shown that initial data for any given pump version may be insufficient; therefore, the Company’s process relies on long-term historical averages until sufficient data are available. As actual experience becomes available, the Company uses the data to update the historical averages. The Company may make further adjustments to the warranty reserve when deemed appropriate, giving additional consideration to the length of time each pump version has been in the field and revised future expectations of performance based on new features and capabilities that may become available through Tandem Device Updater.
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 Amended and Restated 2013 Stock Incentive Plan (2013 Plan) and the fair value of the employees’ purchase rights under the Company’s 2013 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 2013 Plan 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 issued under the 2013 Plan that vest based upon the Company’s actual performance relative to predefined performance metrics is 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, subject to the awardee’s continuing service through the measurement date. 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.
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 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 common stock warrants that are recorded as a liability in the accompanying condensed consolidated balance sheets, the calculation of diluted loss per share requires that, to the extent the average market price of the underlying shares for the reporting period exceeds the exercise price of the warrants and the presumed exercise of the warrants is dilutive to loss per share for the period, an adjustment is made to net loss used in the calculation to remove the change in fair value of the warrants from the numerator for the period. Likewise, an adjustment to the denominator is required to reflect the related dilutive shares, if any, under the treasury stock method.
Recent Accounting Pronouncements	Recent Accounting Pronouncements In June 2020, the FASB issued ASU No. 2020-06, Accounting for Convertible Instruments and Contracts in an Entity’s Own Equity , which is intended to simplify the accounting for convertible instruments. This new guidance eliminated certain models that require separate accounting for embedded conversion features, and eliminated certain of the conditions for equity classification for contracts in an entity’s own equity. Accordingly, a convertible debt instrument will be accounted for as a single liability measured at its amortized cost, as long as no other features require bifurcation and recognition as derivatives. The new guidance could be adopted through either a modified retrospective method of transition or a fully retrospective method of transition. ASU 2020-06 is effective for public business entities for fiscal years beginning after December 15, 2021, including interim periods within those fiscal years. Early adoption is permitted for fiscal years beginning after December 15, 2020, including interim periods within those fiscal years. The Company elected to early adopt the new standard on January 1, 2021 using the modified retrospective method and, accordingly, recorded a net reduction to accumulated deficit of $9.0 million, a decrease to additional paid-in capital of $85.8 million, and an increase to convertible senior notes, net - long-term of $76.8 million to reflect the impact of the accounting change (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, disposable insulin cartridges and infusion sets for the storage and delivery of insulin. The Company views its operations and manages its business as one segment and a single reporting unit because key operating decisions and resource allocations are made by the CODM using consolidated financial data.

Summary of Significant Accoun_2

Summary of Significant Accounting Policies (Tables)	3 Months Ended
	Mar. 31, 2022
Accounting Policies [Abstract]
Schedule of Reconciliation of Change in Estimated Warranty Liabilities	The following table provides a reconciliation of the changes in product warranty liabilities for the three months ended March 31, 2022 and 2021 (in thousands): Three Months Ended March 31, 2022 2021 Balance at beginning of the period $ 30,401 $ 22,075 Provision for warranties issued during the period 7,201 5,896 Settlements made during the period (6,021) (4,256) Decrease in warranty estimates (1,137) (546) Balance at end of the period $ 30,444 $ 23,169 As of March 31, 2022 and December 31, 2021, total product warranty reserves were included in the following consolidated balance sheet accounts (in thousands): March 31, 2022 December 31, 2021 Other current liabilities $ 13,509 $ 13,076 Other long-term liabilities 16,935 17,325 Total warranty reserve $ 30,444 $ 30,401
Schedule of Anti-Dilutive Securities	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): Three Months Ended 2022 2021 Options to purchase common stock 4,424 5,068 Unvested restricted stock units 630 133 Warrants to purchase common stock 211 379 Awards granted under the ESPP 78 78 Convertible senior notes (if-converted) 2,554 2,554 7,897 8,212

Short-Term Investments (Tables)

Short-Term Investments (Tables)	3 Months Ended
	Mar. 31, 2022
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 March 31, 2022 and December 31, 2021 (in thousands): At March 31, 2022 Amortized Gross Unrealized Gross Unrealized Estimated Available-for-sale securities: U.S. Treasury securities $ 296,072 $ 1 $ (2,388) $ 293,685 Commercial paper 156,913 — (202) 156,711 Corporate debt securities 51,649 6 (196) 51,459 U.S. Government-sponsored enterprises 37,217 — (362) 36,855 Supranational bonds 3,000 — — 3,000 Total $ 544,851 $ 7 $ (3,148) $ 541,710 At December 31, 2021 Amortized Gross Unrealized Gross Unrealized Estimated Available-for-sale securities: U.S. Treasury securities $ 222,206 $ — $ (482) $ 221,724 Commercial paper 218,391 14 (24) 218,381 Corporate debt securities 58,881 — (45) 58,836 U.S. Government-sponsored enterprises 50,773 1 (88) 50,686 Supranational bonds 3,003 — — 3,003 Total $ 553,254 $ 15 $ (639) $ 552,630
Schedule of Contractual Maturities of Available - For- Sale Debt Securities	The contractual maturities of available-for-sale debt securities as of March 31, 2022, were as follows (in thousands): Years to Maturity At March 31, 2022 Within One Year One to Two Years Estimated Fair Value U.S. Treasury securities $ 223,643 $ 70,042 $ 293,685 Commercial paper 156,711 — 156,711 Corporate debt securities 43,906 7,553 51,459 U.S. Government-sponsored enterprises 23,612 13,243 36,855 Supranational bonds 3,000 — 3,000 Total $ 450,872 $ 90,838 $ 541,710

Composition of Certain Financ_2

Composition of Certain Financial Statement Items (Tables)	3 Months Ended
	Mar. 31, 2022
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Schedule of Accounts Receivable	Accounts receivable, net consisted of the following at (in thousands): March 31, 2022 December 31, 2021 Accounts receivable $ 98,477 $ 114,974 Less: allowance for credit losses (4,344) (4,249) Accounts receivable, net $ 94,133 $ 110,725
Schedule of Reconciliation of Change in Estimated Allowance for Doubtful Accounts	The following table provides a reconciliation of the changes in the allowance for estimated accounts receivable credit losses for the three months ended March 31, 2022 and 2021 (in thousands): Three Months Ended March 31, 2022 2021 Balance at beginning of the period $ 4,249 $ 3,857 Provision for expected credit losses 846 143 Write-offs and adjustments, net of recoveries (751) (441) Balance at end of the period $ 4,344 $ 3,559
Schedule of Inventory	Inventories consisted of the following at (in thousands): March 31, 2022 December 31, 2021 Raw materials $ 28,223 $ 26,911 Work-in-process 18,520 16,612 Finished goods 33,244 25,028 Total inventories $ 79,987 $ 68,551

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	3 Months Ended
	Mar. 31, 2022
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 March 31, 2022 and December 31, 2021, and indicates the fair value hierarchy of the valuation techniques utilized by the Company to determine such fair value (in thousands): Fair Value Measurements at March 31, 2022 Total Level 1 Level 2 Level 3 Assets Cash equivalents (1) $ 44,905 $ 44,905 $ — $ — U.S. Treasury securities 293,685 293,685 — — Commercial paper 156,711 — 156,711 — Corporate debt securities 51,459 — 51,459 — U.S. Government-sponsored enterprises 36,855 — 36,855 — Supranational bonds 3,000 — 3,000 — Total assets $ 586,615 $ 338,590 $ 248,025 $ — Liabilities Common stock warrants (2) $ 113 $ — $ — $ 113 Total liabilities $ 113 $ — $ — $ 113 Fair Value Measurements at Total Level 1 Level 2 Level 3 Assets Cash equivalents (1) $ 48,286 $ 48,286 $ — $ — U.S. Treasury securities 221,724 221,724 — — Commercial paper 218,381 — 218,381 — Corporate debt securities 58,836 — 58,836 — U.S. Government-sponsored enterprises 50,686 — 50,686 — Supranational bonds 3,003 — 3,003 — Total assets $ 600,916 $ 270,010 $ 330,906 $ — Liabilities Common stock warrants (2) $ 147 $ — $ — $ 147 Total liabilities $ 147 $ — $ — $ 147 (1) Generally, cash equivalents include money market funds and investments with a maturity of three months or less from the date of purchase. (2) Included in other current liabilities on the Company’s condensed consolidated balance sheets.
Schedule of Assumptions Used to Estimate Fair Values of Common Stock Warrants	. The assumptions used to estimate the fair values of the outstanding Series A warrants at March 31, 2022 and December 31, 2021 are presented below: Series A Warrants March 31, 2022 December 31, 2021 Risk-free interest rate 1.1 % 0.3 % Expected dividend yield 0.0% 0.0% Expected volatility 44.4 % 39.1 % Expected term (in years) 0.6 0.8
Schedule of Changes in Fair Value of Total Level 3 Financial Assets	The following table presents a summary of changes in the fair value of the Company’s Level 3 financial liabilities for the three months ended March 31, 2022 and 2021 (in thousands): Three Months Ended March 31, 2022 2021 Balance at beginning of period $ 147 $ 14,261 (Gain) loss recognized from the change in fair value of common stock warrants (34) 690 Common stock warrants exercised during the period — (12,434) Balance at end of period $ 113 $ 2,517

Leases (Tables)

Leases (Tables)	3 Months Ended
	Mar. 31, 2022
Leases [Abstract]
Schedule of Lease Cost	The Company’s lease costs recorded in the condensed consolidated statements of operations were as follows (in thousands): Three Months Ended March 31, 2022 2021 Operating lease cost $ 3,018 $ 2,006 Short-term lease cost 34 22 Total lease cost $ 3,052 $ 2,028 The weighted-average remaining lease term and weighted-average discount rate for operating leases were as follows: March 31, 2022 December 31, 2021 Weighted-average remaining lease term (in years) 11.2 5.0 Weighted-average discount rate used to determine operating lease liabilities 5.4 % 5.6 %
Schedule of Future Minimum Payments Under Non-cancellable Operating Leases	Maturities of operating lease liabilities at March 31, 2022 were as follows (in thousands): Years Ending December 31, 2022 (remaining) $ 6,387 2023 12,805 2024 17,057 2025 17,475 2026 17,528 Thereafter 120,235 Total undiscounted lease payments 191,487 Less: amount representing interest (54,212) Present value of operating lease liabilities 137,275 Less: current portion of operating lease liabilities (8,080) Operating lease liabilities - long-term $ 129,195

Debt (Tables)

Debt (Tables)	3 Months Ended
	Mar. 31, 2022
Debt Disclosure [Abstract]
Schedule of Convertible Notes	The net carrying amount of the Notes on the condensed consolidated balance sheets consisted of the following (in thousands): March 31, 2022 December 31, 2021 Principal amount $ 287,500 $ 287,500 Unamortized debt issuance costs (5,595) (6,033) Net carrying amount $ 281,905 $ 281,467
Schedule of Interest Expense Recognized	The following table details interest expense recognized related to the Notes for the three months ended March 31, 2022 and 2021 (in thousands): Three Months Ended March 31, 2022 March 31, 2021 Contractual interest expense $ 1,078 $ 1,078 Amortization of debt issuance costs 438 428 Total interest expense $ 1,516 $ 1,506

Stockholders' Equity (Tables)

Stockholders' Equity (Tables)	3 Months Ended
	Mar. 31, 2022
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 March 31, 2022 (in thousands): Shares reserved for issuance upon conversion of Convertible Senior Notes 2,554 Shares underlying outstanding warrants 211 Shares underlying outstanding stock options 4,671 Shares underlying unvested restricted stock units 772 Shares authorized for issuance pursuant to awards granted under the ESPP 1,216 Shares authorized for future equity award grants 1,258 Total 10,682
Schedule of Stockholders' Equity Common Stock Warrants	Warrants outstanding to purchase shares of the Company's common stock as of March 31, 2022 were as follows: Issue Date Exercise Price Per Share Warrants Outstanding Expiration Date of Warrants Outstanding October 2017 $3.50 1,000 October 2022 March 2017 $23.50 193,788 March 2027 August 2011 - August 2012 $73.73 16,212 May 2022 - August 2022 211,000
Schedule of Assumptions Used in Black-Scholes Option-Pricing Model	The number of common stock options granted and the respective assumptions used in the Black-Scholes option-pricing model were as follows: Three Months Ended March 31, 2022 2021 Stock options granted — 115,400 Weighted average grant date fair value (per share) N/A $ 60.98 Risk-free interest rate N/A 0.9 % Expected dividend yield N/A 0.0 % Expected volatility N/A 75.6 % Expected term (in years) N/A 6.1
Schedule of Restricted Stock Units	The number of RSUs granted and the respective weighted average grant date fair value were as follows: Three Months Ended 2022 2021 RSUs granted 187,076 3,208 Weighted average grant date fair value (per share) $ 109.97 $ 93.49
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): Three Months Ended March 31, 2022 2021 Cost of sales $ 1,846 $ 1,476 Selling, general & administrative 11,854 9,409 Research and development 4,410 2,062 Total stock-based compensation expense $ 18,110 $ 12,947

Business Segment and Geograph_2

Business Segment and Geographic Information (Tables)	3 Months Ended
	Mar. 31, 2022
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). Three Months Ended March 31, 2022 2021 United States $ 131,283 $ 103,339 Outside the United States 44,624 37,698 Total Sales $ 175,907 $ 141,037

Organization and Basis of Pre_3

Organization and Basis of Presentation (Detail)	3 Months Ended
	Mar. 31, 2022
Insulin Pump | Minimum
Organization And Basis Of Presentation [Line Items]
Expected life span term	4 years

Summary of Significant Accoun_3

Summary of Significant Accounting Policies - Additional Information (Detail) - USD ($)	3 Months Ended		12 Months Ended
	Mar. 31, 2022	Mar. 31, 2021	Dec. 31, 2020	Dec. 31, 2021	Jan. 01, 2021
Summary Of Significant Accounting Policies [Line Items]
Investment owned at cost				$ 8,100,000
Ownership interest of investment owned				5.00%
Finite lived intangible assets impairment loss	$ 0	$ 0
Warranty reserve	30,444,000	$ 23,169,000	$ 22,075,000	$ 30,401,000
Accumulated deficit	(649,310,000)			(634,595,000)
Convertible senior notes, net - long-term	$ 281,905,000			281,467,000
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
Technology-Based Intangible Assets
Summary Of Significant Accounting Policies [Line Items]
Estimated useful life			5 years
Cumulative Effect, Period of Adoption, Adjustment | Accounting Standards Update 2020-06
Summary Of Significant Accounting Policies [Line Items]
Accumulated deficit					$ 9,000,000
Additional paid in capital					(85,800,000)
Convertible senior notes, net - long-term					$ 76,800,000
Convertible senior notes | Level 2 | Convertible senior notes
Summary Of Significant Accounting Policies [Line Items]
Convertible senior notes, fair value	$ 363,300,000			$ 430,000,000

Summary of Significant Accoun_4

Summary of Significant Accounting Policies - Reconciliation of Change in Estimated Warranty Liabilities (Detail) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021	Dec. 31, 2021
Movement in Standard and Extended Product Warranty Accrual, Increase (Decrease) [Roll Forward]
Balance at beginning of the period	$ 30,401	$ 22,075
Provision for warranties issued during the period	7,201	5,896
Settlements made during the period	(6,021)	(4,256)
Decrease in warranty estimates	(1,137)	(546)
Balance at end of the period	30,444	23,169
Other current liabilities	13,509		$ 13,076
Other long-term liabilities	16,935		17,325
Total warranty reserve	$ 30,444	$ 23,169	$ 30,401

Summary of Significant Accoun_5

Summary of Significant Accounting Policies - Anti-Dilutive Securities (Detail) - shares shares in Thousands	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per share, amount (in shares)	7,897	8,212
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)	4,424	5,068
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)	630	133
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)	211	379
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)	78	78
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)	2,554	2,554

Short-Term Investments - Estima

Short-Term Investments - Estimated Fair Value of Short-Term Investments (Detail) - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021
Cash Cash Equivalents And Short Term Investments [Line Items]
Amortized Cost	$ 544,851	$ 553,254
Gross Unrealized Gain	7	15
Gross Unrealized Loss	(3,148)	(639)
Estimated Fair Value	541,710	552,630
U.S. Treasury securities
Cash Cash Equivalents And Short Term Investments [Line Items]
Amortized Cost	296,072	222,206
Gross Unrealized Gain	1	0
Gross Unrealized Loss	(2,388)	(482)
Estimated Fair Value	293,685	221,724
Commercial paper
Cash Cash Equivalents And Short Term Investments [Line Items]
Amortized Cost	156,913	218,391
Gross Unrealized Gain	0	14
Gross Unrealized Loss	(202)	(24)
Estimated Fair Value	156,711	218,381
Corporate debt securities
Cash Cash Equivalents And Short Term Investments [Line Items]
Amortized Cost	51,649	58,881
Gross Unrealized Gain	6	0
Gross Unrealized Loss	(196)	(45)
Estimated Fair Value	51,459	58,836
U.S. Government-sponsored enterprises
Cash Cash Equivalents And Short Term Investments [Line Items]
Amortized Cost	37,217	50,773
Gross Unrealized Gain	0	1
Gross Unrealized Loss	(362)	(88)
Estimated Fair Value	36,855	50,686
Supranational bonds
Cash Cash Equivalents And Short Term Investments [Line Items]
Amortized Cost	3,000	3,003
Gross Unrealized Gain	0	0
Gross Unrealized Loss	0	0
Estimated Fair Value	$ 3,000	$ 3,003

Short-Term Investments - Contra

Short-Term Investments - Contractual Maturities of Available - For- Sale Debt Securities (Details) $ in Thousands	Mar. 31, 2022USD ($)
Cash Cash Equivalents And Short Term Investments [Line Items]
Within One Year	$ 450,872
One to Two Years	90,838
Estimated Fair Value	541,710
U.S. Treasury securities
Cash Cash Equivalents And Short Term Investments [Line Items]
Within One Year	223,643
One to Two Years	70,042
Estimated Fair Value	293,685
Commercial paper
Cash Cash Equivalents And Short Term Investments [Line Items]
Within One Year	156,711
One to Two Years	0
Estimated Fair Value	156,711
Corporate debt securities
Cash Cash Equivalents And Short Term Investments [Line Items]
Within One Year	43,906
One to Two Years	7,553
Estimated Fair Value	51,459
U.S. Government-sponsored enterprises
Cash Cash Equivalents And Short Term Investments [Line Items]
Within One Year	23,612
One to Two Years	13,243
Estimated Fair Value	36,855
Supranational bonds
Cash Cash Equivalents And Short Term Investments [Line Items]
Within One Year	3,000
One to Two Years	0
Estimated Fair Value	$ 3,000

Composition of Certain Financ_3

Composition of Certain Financial Statement Items - Accounts Receivable (Details) - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021	Mar. 31, 2021	Dec. 31, 2020
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Accounts receivable	$ 98,477	$ 114,974
Less: allowance for credit losses	(4,344)	(4,249)	$ (3,559)	$ (3,857)
Accounts receivable, net	$ 94,133	$ 110,725

Composition of Certain Financ_4

Composition of Certain Financial Statement Items - Reconciliation of Change in Estimated Allowance for Doubtful Accounts (Detail) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Allowance for doubtful accounts
Balance at beginning of the period	$ 4,249	$ 3,857
Provision for expected credit losses	846	143
Write-offs and adjustments, net of recoveries	(751)	(441)
Balance at end of the period	$ 4,344	$ 3,559

Composition of Certain Financ_5

Composition of Certain Financial Statement Items - Inventory (Detail) - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Raw materials	$ 28,223	$ 26,911
Work-in-process	18,520	16,612
Finished goods	33,244	25,028
Total inventories	$ 79,987	$ 68,551

Fair Value Measurements - Finan

Fair Value Measurements - Financial Assets and Liabilities Measured at Fair Value on Recurring Basis (Detail) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2022	Dec. 31, 2021
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt securities, available for sale	$ 541,710	$ 552,630
Maximum
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash equivalents maturity term	3 months
U.S. Treasury securities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt securities, available for sale	$ 293,685	221,724
Commercial paper
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt securities, available for sale	156,711	218,381
Corporate debt securities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt securities, available for sale	51,459	58,836
Supranational bonds
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt securities, available for sale	3,000	3,003
Fair Value, Measurements, Recurring
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total assets	586,615	600,916
Common stock warrants	113	147
Total liabilities	113	147
Fair Value, Measurements, Recurring | Cash equivalents
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash equivalents	44,905	48,286
Fair Value, Measurements, Recurring | U.S. Treasury securities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt securities, available for sale	293,685	221,724
Fair Value, Measurements, Recurring | Commercial paper
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash equivalents	156,711	218,381
Fair Value, Measurements, Recurring | Corporate debt securities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt securities, available for sale	51,459	58,836
Fair Value, Measurements, Recurring | U.S. Government-sponsored enterprises
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt securities, available for sale	36,855	50,686
Fair Value, Measurements, Recurring | Supranational bonds
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt securities, available for sale	3,000	3,003
Fair Value, Measurements, Recurring | Level 1
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total assets	338,590	270,010
Common stock warrants	0	0
Total liabilities	0	0
Fair Value, Measurements, Recurring | Level 1 | Cash equivalents
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash equivalents	44,905	48,286
Fair Value, Measurements, Recurring | Level 1 | U.S. Treasury securities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt securities, available for sale	293,685	221,724
Fair Value, Measurements, Recurring | Level 1 | Commercial paper
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash equivalents	0	0
Fair Value, Measurements, Recurring | Level 1 | Corporate debt securities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt securities, available for sale	0	0
Fair Value, Measurements, Recurring | Level 1 | U.S. Government-sponsored enterprises
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt securities, available for sale	0	0
Fair Value, Measurements, Recurring | Level 1 | Supranational bonds
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt securities, available for sale	0	0
Fair Value, Measurements, Recurring | Level 2
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total assets	248,025	330,906
Common stock warrants	0	0
Total liabilities	0	0
Fair Value, Measurements, Recurring | Level 2 | Cash equivalents
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash equivalents	0	0
Fair Value, Measurements, Recurring | Level 2 | U.S. Treasury securities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt securities, available for sale	0	0
Fair Value, Measurements, Recurring | Level 2 | Commercial paper
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash equivalents	156,711	218,381
Fair Value, Measurements, Recurring | Level 2 | Corporate debt securities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt securities, available for sale	51,459	58,836
Fair Value, Measurements, Recurring | Level 2 | U.S. Government-sponsored enterprises
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt securities, available for sale	36,855	50,686
Fair Value, Measurements, Recurring | Level 2 | Supranational bonds
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt securities, available for sale	3,000	3,003
Fair Value, Measurements, Recurring | Level 3
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total assets	0	0
Common stock warrants	113	147
Total liabilities	113	147
Fair Value, Measurements, Recurring | Level 3 | Cash equivalents
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash equivalents	0	0
Fair Value, Measurements, Recurring | Level 3 | U.S. Treasury securities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt securities, available for sale	0	0
Fair Value, Measurements, Recurring | Level 3 | Commercial paper
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash equivalents	0	0
Fair Value, Measurements, Recurring | Level 3 | Corporate debt securities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt securities, available for sale	0	0
Fair Value, Measurements, Recurring | Level 3 | U.S. Government-sponsored enterprises
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt securities, available for sale	0	0
Fair Value, Measurements, Recurring | Level 3 | Supranational bonds
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt securities, available for sale	$ 0	$ 0

Fair Value Measurements - Addit

Fair Value Measurements - Additional Information (Detail) - $ / shares	Mar. 31, 2022	Dec. 31, 2021
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Outstanding warrants (in shares)	211,000
Common Stock Warrant Expiring October 2022
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Warrants exercise price (in dollars per share)	$ 3.50
Outstanding warrants (in shares)	1,000	1,000

Fair Value Measurements - Assum

Fair Value Measurements - Assumptions Used to Estimate Fair Values of Common Stock Warrants (Detail) - Series A Warrants	Mar. 31, 2022	Dec. 31, 2021
Risk-free interest rate
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Warrants outstanding, measurement input	0.011	0.003
Expected dividend yield
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Warrants outstanding, measurement input	0	0
Expected volatility
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Warrants outstanding, measurement input	0.444	0.391
Expected term (in years)
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Expected term (in years)	7 months 6 days	9 months 18 days

Fair Value Measurements - Chang

Fair Value Measurements - Changes in Fair Value of Total Level 3 Financial Assets (Detail) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance at beginning of period	$ 147	$ 14,261
(Gain) loss recognized from the change in fair value of common stock warrants	(34)	690
Common stock warrants exercised during the period	0	(12,434)
Balance at end of period	$ 113	$ 2,517

Leases - Additional Information

Leases - Additional Information (Details) $ in Thousands	3 Months Ended
	Mar. 31, 2022USD ($)ft²extension	Mar. 31, 2021USD ($)ft²extension	Jun. 30, 2022USD ($)	Dec. 31, 2021USD ($)	Sep. 30, 2021ft²	May 31, 2021ft²
Lessee, Lease, Description [Line Items]
Operating lease right-of-use assets	$ 131,058			$ 27,503
Operating lease, liability	137,275
Operating lease, payments	3,400	$ 2,300
Total future minimum lease payments	191,487
Vista Sorrento Parkway Lease
Lessee, Lease, Description [Line Items]
Operating lease, number of options to extend | extension		2
Operating lease extension period		5 years
Operating lease right-of-use assets	107,500	$ 15,100
Operating lease, liability	$ 107,500	$ 15,100
Vista Sorrento Parkway Lease, Existing Premises
Lessee, Lease, Description [Line Items]
Area of office space leased | ft²		59,013
Vista Sorrento Parkway Lease, Expansion Space
Lessee, Lease, Description [Line Items]
Area of office space leased | ft²		14,916
Tech Center Lease
Lessee, Lease, Description [Line Items]
Area of office space leased | ft²	34,569				181,949
Operating lease, number of options to extend | extension	2
Annual percentage increase in monthly base rent	3.00%
Tech Center Lease Phase I
Lessee, Lease, Description [Line Items]
Area of office space leased | ft²	77,458				143,850
Operating lease extension period	5 years
Monthly base rent	$ 906
Beginning period after initial lease term for which no rent is due	2 months
Ending period for which no rent is due	9 months
Tech Center Lease Phase II
Lessee, Lease, Description [Line Items]
Area of office space leased | ft²					38,099
Increase in monthly base rent	$ 255
Beginning period after initial lease term for which no rent is due	2 months
Ending period for which no rent is due	5 months
Total future minimum lease payments	$ 34,700
High Bluff Drive Lease
Lessee, Lease, Description [Line Items]
Area of office space leased | ft²						31,372
High Bluff Drive Lease | Forecast
Lessee, Lease, Description [Line Items]
Operating lease right-of-use assets			$ 3,000
Operating lease, liability			$ 3,000
Minimum
Lessee, Lease, Description [Line Items]
Lease term	2 years
Maximum
Lessee, Lease, Description [Line Items]
Lease term	13 years

Leases - Lease Cost, Lease Term

Leases - Lease Cost, Lease Term Discount Rate ,Operating Leases (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021	Dec. 31, 2021
Leases [Abstract]
Operating lease cost	$ 3,018	$ 2,006
Short-term lease cost	34	22
Total lease cost	$ 3,052	$ 2,028
Weighted-average remaining lease term (in years)	11 years 2 months 12 days		5 years
Weighted-average discount rate used to determine operating lease liabilities	5.40%		5.60%

Leases - Future Minimum Payment

Leases - Future Minimum Payments Under Non-cancellable Operating Leases (Details) - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021
Leases [Abstract]
2022 (remaining)	$ 6,387
2023	12,805
2024	17,057
2025	17,475
2026	17,528
Thereafter	120,235
Total undiscounted lease payments	191,487
Less: amount representing interest	(54,212)
Present value of operating lease liabilities	137,275
Less: current portion of operating lease liabilities	(8,080)	$ (9,279)
Operating lease liabilities - long-term	$ 129,195	$ 23,922

Debt - Convertible Senior Notes

Debt - Convertible Senior Notes Additional Information (Detail) - Convertible senior notes - Convertible senior notes	1 Months Ended	3 Months Ended	12 Months Ended
	May 31, 2020USD ($)trading_day$ / shares	Mar. 31, 2022USD ($)$ / shares	Dec. 31, 2021USD ($)	May 12, 2020$ / shares
Debt Instrument [Line Items]
Principal | $	$ 287,500,000	$ 287,500,000	$ 287,500,000
Interest rate	1.50%
Net proceeds from issuance of convertible notes | $	$ 244,600,000
Debt instrument, convertible, conversion ratio	0.0088836
Conversion price (in dollars per share) | $ / shares	$ 112.57
Debt instrument, convertible, threshold trading days	20
Debt instrument, convertible, threshold trading days consecutive trading days	30
Redemption price percentage	100.00%
Unamortized debt issuance costs | $		$ 5,595,000	6,033,000
Effective interest rate		2.20%
Remaining debt term		3 years
Principal amount | $		$ 9,500,000	$ 96,900,000
Capped call transactions net cost | $	$ 34,100,000
Debt instrument, initial cap price per share (in dollars per share) | $ / shares	$ 173.18
Stock price per share (in dollars per share) | $ / shares				$ 86.59
Conversion Instance, 130%
Debt Instrument [Line Items]
Debt instrument, convertible, threshold trading days	20
Debt instrument, convertible, threshold trading days consecutive trading days	30
Conversion Instance, 98%
Debt Instrument [Line Items]
Debt instrument, convertible, threshold trading days	5
Debt instrument, convertible, threshold trading days consecutive trading days	5
Minimum
Debt Instrument [Line Items]
Conversion price (in dollars per share) | $ / shares	$ 112.57	$ 112.57
Debt instrument, convertible, threshold percentage of stock price trigger	130.00%
Minimum | Conversion Instance, 130%
Debt Instrument [Line Items]
Debt instrument, convertible, threshold percentage of stock price trigger	130.00%
Minimum | Conversion Instance, 98%
Debt Instrument [Line Items]
Debt instrument, convertible, threshold percentage of stock price trigger	98.00%
Maximum
Debt Instrument [Line Items]
Conversion price (in dollars per share) | $ / shares	$ 173.18

Debt - Components of Convertibl

Debt - Components of Convertible Note (Details) - Convertible senior notes - Convertible senior notes - USD ($)	Mar. 31, 2022	Dec. 31, 2021	May 31, 2020
Debt Instrument [Line Items]
Principal amount	$ 287,500,000	$ 287,500,000	$ 287,500,000
Unamortized debt issuance costs	(5,595,000)	(6,033,000)
Net carrying amount	$ 281,905,000	$ 281,467,000

Debt - Interest Expense Recogni

Debt - Interest Expense Recognized (Details) - Convertible senior notes - Convertible senior notes - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Debt Instrument [Line Items]
Contractual interest expense	$ 1,078	$ 1,078
Amortization of debt issuance costs	438	428
Total interest expense	$ 1,516	$ 1,506

Stockholders' Equity -Shares of

Stockholders' Equity -Shares of Common Stock Reserved for Future Issuance (Detail) shares in Thousands	Mar. 31, 2022shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock reserved for future issuance (in shares)	10,682
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)	2,554
Shares underlying outstanding warrants
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock reserved for future issuance (in shares)	211
Shares underlying outstanding stock options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock reserved for future issuance (in shares)	4,671
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)	772
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)	1,216
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)	1,258

Stockholders' Equity - Common S

Stockholders' Equity - Common Stock Warrants (Details) - $ / shares	Mar. 31, 2022	Dec. 31, 2021
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Outstanding warrants (in shares)	211,000
Common Stock Warrant Expiring October 2022
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Warrants exercise price (in dollars per share)	$ 3.50
Outstanding warrants (in shares)	1,000	1,000
Common Stock Warrant Expiring March 2027
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Warrants exercise price (in dollars per share)	$ 23.50
Outstanding warrants (in shares)	193,788
Common Stock Warrant Expiring Between March 2022 and August 2022
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Warrants exercise price (in dollars per share)	$ 73.73
Outstanding warrants (in shares)	16,212

Stockholders' Equity - Addition

Stockholders' Equity - Additional Information (Detail) $ in Millions	1 Months Ended		3 Months Ended		12 Months Ended
	Mar. 31, 2022segmentshares	Feb. 28, 2022	Mar. 31, 2022USD ($)segmentshares	Mar. 31, 2021shares	Dec. 31, 2021USD ($)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares issued by each warrant	1		1
Total stock-based compensation expense capitalized as part of cost of inventory | $			$ 0.8		$ 1
Awards to be granted under the ESPP
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Offering period			2 years
Number of purchase periods | segment	4		4
Purchase period			6 months
Purchase of common stock under ESPP (in shares)			0	0
Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	3 years	4 years
Restricted Stock Units (RSUs) | Tranche One
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock vested percentage	33.00%
Restricted Stock Units (RSUs) | Tranche Two
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	2 years	3 years
Stock vested percentage		25.00%
Share-based Payment Arrangement, Option
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period			4 years
Vesting period of remaining stock (in years)			3 years
Maximum term of stock options (in years)			10 years
Share-based Payment Arrangement, Option | Tranche One
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock vested percentage			25.00%
Warrants to purchase common stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Warrants issue to purchase common stock (in shares)	1,835		1,835	125,000

Stockholders' Equity - Assumpti

Stockholders' Equity - Assumptions Used in Black-Scholes Option-Pricing Model (Detail) - Share-based Payment Arrangement, Option - $ / shares	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares granted (in shares)	0	115,400
Weighted average grant date fair value (per share)		$ 60.98
Risk-free interest rate		0.90%
Expected dividend yield		0.00%
Expected volatility		75.60%
Expected term (in years)		6 years 1 month 6 days

Stockholders' Equity - Restrict

Stockholders' Equity - Restricted Stock Units (RSUs) (Detail) - Restricted Stock Units (RSUs) - $ / shares	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward]
Granted (in shares)	187,076	3,208
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract]
Weighted average grant date fair value (in dollars per share)	$ 109.97	$ 93.49

Stockholders' Equity - Allocati

Stockholders' Equity - Allocation of Stock-Based Compensation Expense (Detail) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation expense	$ 18,110	$ 12,947
Cost of sales
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation expense	1,846	1,476
Selling, general & administrative
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation expense	11,854	9,409
Research and development
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation expense	$ 4,410	$ 2,062

Employee-Benefits - Additional

Employee-Benefits - Additional Information (Detail)	3 Months Ended
	Mar. 31, 2022
Retirement Benefits [Abstract]
Minimum age of employees for defined contribution plan	18 years

Income Taxes - Additional Infor

Income Taxes - Additional Information (Detail) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Income Tax Disclosure [Abstract]
Income tax expense (benefit)	$ (1,724)	$ (117)
Income (loss) before taxes	$ (16,439)	$ (5,161)

Business Segment and Geograph_3

Business Segment and Geographic Information - Additional Information (Detail) - segment	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Revenue, Major Customer [Line Items]
Number of operating segments	1
United States | Revenue from Contract with Customer Benchmark | Customer Concentration Risk
Revenue, Major Customer [Line Items]
Customers accounted for 10% or more	65.00%	68.00%
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%	96.00%

Business Segment and Geograph_4

Business Segment and Geographic Information - Geographical Markets (Detail) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Disaggregation of Revenue [Line Items]
Total Sales	$ 175,907	$ 141,037
United States
Disaggregation of Revenue [Line Items]
Total Sales	131,283	103,339
Outside the United States
Disaggregation of Revenue [Line Items]
Total Sales	$ 44,624	$ 37,698

Commitments and Contingencies (

Commitments and Contingencies (Detail) $ in Millions	Mar. 29, 2021Plaintiff	Jul. 24, 2020lawsuit	May 31, 2020lawsuit	Mar. 31, 2022USD ($)legal_matter
Commitments and Contingencies Disclosure [Abstract]
Number of lawsuits | lawsuit		3	3
Loss contingency, number of plaintiffs | Plaintiff	3
Number of legal proceedings regulatory matters or other disputes or claims | legal_matter				0
Unsecured letter of credit outstanding | $				$ 4.9

Uncategorized Items - tndm-2022

Label	Element	Value
Accounting Standards Update [Extensible Enumeration]	us-gaap_AccountingStandardsUpdateExtensibleList	Accounting Standards Update 2020-06 [Member]