Insulet (PODD) 10-Q 6 Aug 19 2019 Q2 Quarterly report Financial data

Document and Entity Information

Document and Entity Information - shares	6 Months Ended
	Jun. 30, 2019	Jul. 25, 2019
Cover page.
Entity Incorporation, State or Country Code	DE
Title of 12(b) Security	Common Stock, $0.01 Par Value Per Share
Document Transition Report	false
Document Quarterly Report	true
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Jun. 30, 2019
Document Fiscal Year Focus	2019
Document Fiscal Period Focus	Q2
Trading Symbol	PODD
Entity Registrant Name	INSULET CORPORATION
Entity File Number	001-33462
Entity Central Index Key	0001145197
Current Fiscal Year End Date	--12-31
Entity Filer Category	Large Accelerated Filer
Entity Emerging Growth Company	false
Entity Small Business	false
Entity Current Reporting Status	Yes
Entity Shell Company	false
Entity Common Stock, Shares Outstanding (in shares)		60,271,673
Security Exchange Name	NASDAQ
City Area Code	978
Entity Interactive Data Current	Yes
Local Phone Number	600-7000
Entity Tax Identification Number	04-3523891
Entity Address, Address Line One	100 Nagog Park
Entity Address, City or Town	Acton
Entity Address, State or Province	MA
Entity Address, Postal Zip Code	01720

Consolidated Balance Sheets

Consolidated Balance Sheets - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018
Current Assets
Cash and cash equivalents	$ 119,867	$ 113,906
Short-term investments	189,881	175,040
Accounts receivable trade, less allowance for doubtful accounts of $4,098 and $3,610	66,958	63,294
Unbilled receivable	11,781	13,378
Inventories	85,109	71,414
Prepaid expenses and other current assets	25,211	24,254
Total current assets	498,807	461,286
Long-term investments	62,677	140,784
Property and equipment, net	334,025	258,379
Other intangible assets, net	13,040	10,383
Goodwill	39,739	39,646
Other assets	29,435	18,266
Total assets	977,723	928,744
Current Liabilities
Accounts payable	24,752	25,500
Accrued expenses and other current liabilities	81,021	90,157
Total current liabilities	105,773	115,657
Convertible debt, net of current portion	607,351	591,978
Other liabilities	14,819	9,010
Total liabilities	727,943	716,645
Stockholders’ Equity
Preferred stock, $.001 par value, 5,000,000 authorized; none issued and outstanding	0	0
Common stock, $.001 par value, 100,000,000 authorized; 60,149,926 and 59,188,758 issued and outstanding	60	59
Additional paid-in capital	930,383	898,559
Accumulated other comprehensive loss	(2,829)	(2,905)
Accumulated deficit	(677,834)	(683,614)
Total stockholders’ equity	249,780	212,099
Total liabilities and stockholders’ equity	$ 977,723	$ 928,744

Consolidated Balance Sheets (Pa

Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018
Statement of Financial Position [Abstract]
Allowance for doubtful accounts	$ 4,098	$ 3,610
Preferred stock, par value (in dollars per share)	$ 0.001	$ 0.001
Preferred stock, authorized (in shares)	5,000,000	5,000,000
Preferred stock, issued (in shares)	0	0
Preferred stock, outstanding (in shares)	0	0
Common stock, par value (in dollars per share)	$ 0.001	$ 0.001
Common stock, authorized (in shares)	100,000,000	100,000,000
Common stock, issued (in shares)	60,149,926	59,188,758
Common stock, outstanding (in shares)	60,149,926	59,188,758

Consolidated Statements of Oper

Consolidated Statements of Operations - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Income Statement [Abstract]
Revenue	$ 177,136	$ 124,262	$ 336,691	$ 247,840
Cost of revenue	60,718	42,190	113,577	89,953
Gross profit	116,418	82,072	223,114	157,887
Operating expenses:
Research and development	32,264	18,801	64,218	39,068
Sales and marketing	47,401	36,575	89,017	69,624
General and administrative	29,150	22,371	55,011	44,870
Total operating expenses	108,815	77,747	208,246	153,562
Operating income	7,603	4,325	14,868	4,325
Interest expense, net of portion capitalized	(7,642)	(7,290)	(14,257)	(15,208)
Other income, net	1,923	1,686	5,977	3,368
Income (loss) before income taxes	1,884	(1,279)	6,588	(7,515)
Income tax expense	482	412	808	745
Net income (loss)	$ 1,402	$ (1,691)	$ 5,780	$ (8,260)
Net income (loss) per share:
Net income (loss) per share: basic (in dollars per share)	$ 0.02	$ (0.03)	$ 0.10	$ (0.14)
Net income (loss) per shares: diluted (in dollars per share)	$ 0.02	$ (0.03)	$ 0.09	$ (0.14)
Weighted average number of shares outstanding, basic (in shares)	59,844,991	58,833,498	59,601,365	58,659,111
Weighted average number of shares outstanding, diluted (in shares)	61,486,325	58,833,498	61,332,451	58,659,111

Consolidated Statements of Comp

Consolidated Statements of Comprehensive Income (Loss) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Statement of Comprehensive Income [Abstract]
Net income (loss)	$ 1,402	$ (1,691)	$ 5,780	$ (8,260)
Other comprehensive income (loss), net of tax
Foreign currency translation adjustment, net of tax	(359)	(741)	(1,174)	(1,059)
Unrealized gain (loss) on available-for-sale debt securities, net of tax	615	(109)	1,250	(834)
Total other comprehensive income (loss), net of tax	256	(850)	76	(1,893)
Total comprehensive income (loss)	$ 1,658	$ (2,541)	$ 5,856	$ (10,153)

Consolidated Statements of Stoc

Consolidated Statements of Stockholders' Equity - USD ($) $ in Thousands	Total	Common Stock	Additional Paid-in Capital	Accumulated Deficit	Accumulated Other Comprehensive Loss
Beginning balance (in shares) at Dec. 31, 2017		58,319,348
Beginning balance at Dec. 31, 2017	$ 158,516	$ 58	$ 866,206	$ (707,255)	$ (493)
Exercise of options to purchase common stock (in shares)		308,369
Exercise of options to purchase common stock	9,741		9,741
Issuance for employee stock purchase plan (in shares)		24,643
Issuance for employee stock purchase plan	1,481		1,481
Stock-based compensation expense	15,117		15,117
Restricted stock units vested, net of shares withheld for taxes (in shares)		323,035
Restricted stock units vested, net of shares withheld for taxes	(12,691)	$ 1	(12,692)
Debt retirement	(3,212)		(3,212)
Net income (loss)	(8,260)			(8,260)
Other comprehensive income (loss)	(1,893)				(1,893)
Ending balance (in shares) at Jun. 30, 2018		58,975,395
Ending balance at Jun. 30, 2018	179,148	$ 59	876,641	(695,166)	(2,386)
Beginning balance (in shares) at Mar. 31, 2018		58,723,242
Beginning balance at Mar. 31, 2018	170,568	$ 59	865,520	(693,475)	(1,536)
Exercise of options to purchase common stock (in shares)		194,327
Exercise of options to purchase common stock	6,780		6,780
Issuance for employee stock purchase plan (in shares)		24,643
Issuance for employee stock purchase plan	1,481		1,481
Stock-based compensation expense	6,936		6,936
Restricted stock units vested, net of shares withheld for taxes (in shares)		33,183
Restricted stock units vested, net of shares withheld for taxes	(876)		(876)
Debt retirement	(3,200)		(3,200)
Net income (loss)	(1,691)			(1,691)
Other comprehensive income (loss)	(850)				(850)
Ending balance (in shares) at Jun. 30, 2018		58,975,395
Ending balance at Jun. 30, 2018	$ 179,148	$ 59	876,641	(695,166)	(2,386)
Beginning balance (in shares) at Dec. 31, 2018	59,188,758	59,188,758
Beginning balance at Dec. 31, 2018	$ 212,099	$ 59	898,559	(683,614)	(2,905)
Exercise of options to purchase common stock (in shares)	721,041	716,687
Exercise of options to purchase common stock	$ 23,660	$ 1	23,659
Issuance for employee stock purchase plan (in shares)		27,613
Issuance for employee stock purchase plan	2,030		2,030
Stock-based compensation expense	14,078		14,078
Restricted stock units vested, net of shares withheld for taxes (in shares)		216,868
Restricted stock units vested, net of shares withheld for taxes	(7,943)		(7,943)
Net income (loss)	5,780			5,780
Other comprehensive income (loss)	$ 76				76
Ending balance (in shares) at Jun. 30, 2019	60,149,926	60,149,926
Ending balance at Jun. 30, 2019	$ 249,780	$ 60	930,383	(677,834)	(2,829)
Beginning balance (in shares) at Mar. 31, 2019		59,638,439
Beginning balance at Mar. 31, 2019	223,630	$ 60	905,891	(679,236)	(3,085)
Exercise of options to purchase common stock (in shares)		447,214
Exercise of options to purchase common stock	14,599		14,599
Issuance for employee stock purchase plan (in shares)		27,613
Issuance for employee stock purchase plan	2,030		2,030
Stock-based compensation expense	8,294		8,294
Restricted stock units vested, net of shares withheld for taxes (in shares)		36,660
Restricted stock units vested, net of shares withheld for taxes	(431)		(431)
Net income (loss)	1,402			1,402
Other comprehensive income (loss)	$ 256				256
Ending balance (in shares) at Jun. 30, 2019	60,149,926	60,149,926
Ending balance at Jun. 30, 2019	$ 249,780	$ 60	$ 930,383	$ (677,834)	$ (2,829)

Consolidated Statements of Cash

Consolidated Statements of Cash Flows - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018
Cash flows from operating activities
Net income (loss)	$ 5,780	$ (8,260)
Adjustments to reconcile net income (loss) to net cash provided by (used in) operating activities
Depreciation and amortization	11,026	7,131
Non-cash interest expense	15,372	14,427
Stock-based compensation expense	14,078	15,117
Provision for bad debts	1,969	1,586
Other	(589)	(130)
Changes in operating assets and liabilities:
Accounts receivable and unbilled receivable	(5,406)	(7,217)
Inventories	(14,005)	(7,959)
Prepaid expenses and other assets	(3,076)	(4,823)
Accounts payable, accrued expenses and other current liabilities	(3,749)	(17,873)
Deferred revenue	190	(2,626)
Other liabilities	(1,313)	232
Net cash provided by (used in) operating activities	20,277	(10,395)
Cash flows from investing activities
Purchases of property, equipment	(91,949)	(87,730)
Acquisition of intangible assets	(4,965)	(2,207)
Purchases of investments	(39,065)	(117,940)
Receipts from the maturity or sale of investments	104,186	90,774
Net cash used in investing activities	(31,793)	(117,103)
Cash flows from financing activities
Repayment of convertible debt	0	(6,687)
Proceeds from exercise of stock options and issuance of common stock under employee stock purchase plan	25,690	11,206
Payments for taxes related to net share settlement of equity awards	(7,943)	(12,691)
Net cash provided by (used in) financing activities	17,747	(8,172)
Effect of exchange rate changes on cash	(270)	(661)
Net increase (decrease) in cash, cash equivalents and restricted cash	5,961	(136,331)
Cash, cash equivalents and restricted cash at beginning of period	113,906	272,577
Cash, cash equivalents and restricted cash at end of period	119,867	136,246
Non-cash investing and financing activities:
Purchases of property and equipment included in accounts payable and accrued expenses	$ 3,051	$ 12,300

Nature of the Business

Nature of the Business	6 Months Ended
	Jun. 30, 2019
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Nature of the Business	Nature of the Business Insulet Corporation (“Insulet”) is primarily engaged in the development, manufacturing and sale of its proprietary Omnipod ® System, an innovative, discreet and easy-to-use continuous insulin delivery system for people with insulin-dependent diabetes. The Omnipod System consists of two product lines: the Omnipod Insulin Management System (“Omnipod”), which Insulet has been selling since 2005, and its next generation Omnipod DASH TM Insulin Management System (“Omnipod DASH” or “DASH”). Insulet began a full market release of Omnipod DASH in the United States at the end of the first quarter of 2019. Collectively, these products are referred to as the “Omnipod System”. In addition to using the Omnipod System for insulin delivery, Insulet also partners with global pharmaceutical and biotechnology companies to tailor the Omnipod System technology platform for the delivery of their drugs across other therapeutic areas. The majority of Insulet's drug delivery revenue currently consists of sales to Amgen supplying the Neulasta ® Onpro ®

Basis of Presentation

Basis of Presentation	6 Months Ended
	Jun. 30, 2019
Accounting Policies [Abstract]
Basis of Presentation	Basis of Presentation Basis of Presentation The accompanying financial statements reflect the consolidated operations of Insulet and its subsidiaries (the “Company”). The unaudited consolidated financial statements have been prepared in accordance with generally accepted accounting principles in the United States of America (“U.S. GAAP”). The preparation of financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions in the application of certain of its significant accounting policies that may materially affect the reported amounts of assets, liabilities, equity, revenue and expenses. Actual results may differ from those estimates. In management's opinion, the unaudited consolidated financial statements contain all normal recurring adjustments necessary for a fair statement of the interim results reported. Operating results for the three and six months ended June 30, 2019 are not necessarily indicative of the results that may be expected for the full year ending December 31, 2019 , or for any other subsequent interim period. The year-end balance sheet data was derived from audited consolidated financial statements. These consolidated financial statements do not include all of the annual disclosures required by U.S. GAAP; accordingly, they should be read in conjunction with the Company’s audited consolidated financial statements contained in the Company’s Annual Report on Form 10-K for the year ended December 31, 2018 . Shipping and Handling Costs Shipping and handling costs are included in general and administrative expenses and were $2.3 million and $1.4 million for the three months ended June 30, 2019 and 2018 , respectively, and were $4.9 million and $2.5 million for the six months ended June 30, 2019 and 2018 , respectively. Reclassification of Prior Period Amounts Certain reclassifications have been made to prior period amounts to conform to the current period financial statement presentation. Software license costs have been reallocated from general and administrative expenses to research and development and sales and marketing expenses based on license usage. These reclassifications have no effect on previously reported net income. Recently Adopted Accounting Standards Effective January 1, 2019, the Company adopted Accounting Standards Update (“ASU”) No. 2016-02, Leases (Topic 842) (“ASU 2016-02”). ASU 2016-02 and its related amendments (collectively referred to as ASC 842), which amends the guidance in former ASC Topic 840, Leases. The new standard requires lessees to recognize right-of-use (“ROU”) assets and lease liabilities on the balance sheet for those leases classified as operating leases. The Company adopted ASC 842 on January 1, 2019 using the modified retrospective method, whereby the new guidance is applied prospectively as of the date of adoption and prior periods are not restated. The Company elected the practical expedients that permit the Company to not reassess (1) whether any expired or existing contracts are or contain leases, (2) the lease classification for any expired or existing leases, and (3) any initial direct costs for any existing leases as of the effective date. The Company also excludes leases with an expected term of less than one year from the application of ASC 842. Adoption of the lease standard had a material impact on the Company's consolidated balance sheet, which is disclosed in Note 11 . Effective January 1, 2019, the Company early adopted ASU 2018-15, Customer's Accounting for Implementation Costs Incurred in a Cloud Computing Arrangement That Is a Service Contract (“ASU 2018-15”). ASU 2018-15 requires certain costs to implement a cloud computing arrangement that is a service contract to be capitalized consistent with the rules applicable to internal-use software capitalization projects. The Company adopted this new guidance effective January 1, 2019, prospectively. The Company defers eligible costs related to the implementation of cloud computing arrangements within other current and non-current assets and amortizes such costs over the expected term of the hosting arrangement to the same income statement line as the associated cloud operating expenses. Adoption of this standard resulted in the Company capitalizing $0.7 million and $2.0 million of cloud computing implementation costs for the three and six months ended June 30, 2019 , respectively.

Revenue and Contract Acquisitio

Revenue and Contract Acquisition Costs	6 Months Ended
	Jun. 30, 2019
Revenue from Contract with Customer [Abstract]
Revenue and Contract Acquisition Costs	Revenue and Contract Acquisition Costs The following table summarizes revenue from contracts with customers for the three and six months ended June 30, 2019 and 2018 : Three Months Ended June 30, Six Months Ended June 30, (in thousands) 2019 2018 2019 2018 U.S. Omnipod $ 98,074 $ 78,047 $ 184,177 $ 148,319 International Omnipod 62,736 28,509 119,624 66,913 Total Diabetes Revenue 160,810 106,556 303,801 215,232 Drug Delivery 16,326 17,706 32,890 32,608 Total $ 177,136 $ 124,262 $ 336,691 $ 247,840 Revenue for customers comprising more than 10% of total revenue were as follows: Three Months Ended June 30, Six Months Ended June 30, 2019 2018 2019 2018 Amgen, Inc. * 14% 10% 13% Ypsomed * * * 17% Cardinal Health Inc. and affiliates 12% 13% 11% 12% * Represents less than 10% of consolidated revenue. Deferred revenue related to unsatisfied performance obligations was included in the following consolidated balance sheet accounts in the amounts shown: As of (in thousands) June 30, 2019 December 31, 2018 Accrued expenses and other current liabilities $ 1,374 $ 1,184 Other liabilities 986 931 Total deferred revenue $ 2,360 $ 2,115 Revenue recognized during the three and six months ended June 30, 2019 included in deferred revenue at the beginning of 2019 was $0.2 million and $1.1 million , respectively. Revenue recognized during the three and six months ended June 30, 2018 included in deferred revenue at the beginning of 2018 was $ 1.1 million and $2.4 million , respectively. No revenue was recognized during the three and six months ended June 30, 2019 and 2018 from performance obligations satisfied or partially satisfied in previous periods. Contract acquisition costs, representing capitalized commissions costs related to new patient starts, net of amortization, were included in the following consolidated balance sheet accounts in the amounts shown: As of (in thousands) June 30, 2019 December 31, 2018 Prepaid expenses and other current assets $ 8,452 $ 7,277 Other assets 18,183 15,988 Total capitalized contract acquisition costs, net $ 26,635 $ 23,265 The Company recognized $2.1 million and $4.1 million of amortization of capitalized contract acquisition costs during the three and six months ended June 30, 2019 , respectively.

Investments

Investments	6 Months Ended
	Jun. 30, 2019
Investments, Debt and Equity Securities [Abstract]
Investments	Investments Cash and Cash Equivalents Included in the Company's cash and cash equivalents are restricted cash amounts set aside for collateral on outstanding letters of credit totaling $2.7 million at both June 30, 2019 and December 31, 2018 . Marketable Securities The Company's short-term and long-term investments in debt securities had maturity dates that range from 8 days to 23 months as of June 30, 2019 . The Company’s investment portfolio included approximately 40 available-for-sale debt securities that had insignificant unrealized loss positions as of June 30, 2019 and December 31, 2018 . The Company's investments had insignificant realized gains or losses for both the three and six months ended June 30, 2019 and June 30, 2018. The Company uses the following fair value hierarchy to measure the fair value of assets and liabilities: Level 1 — quoted prices in active markets for identical assets or liabilities; Level 2 — observable inputs other than quoted prices in active markets for identical assets or liabilities; Level 3 — unobservable inputs for which there is little or no market data, which require the Company to develop its own assumptions. The Company had no Level 3 assets or liabilities as of June 30, 2019 and December 31, 2018 . The following table provides amortized cost, gross unrealized gains and losses, fair value and the level in the fair value hierarchy for the Company's investments as of June 30, 2019 and December 31, 2018: (in thousands) Amortized Cost Gross Unrealized Gains Gross Unrealized (Losses) Fair Value Level 1 Level 2 June 30, 2019 Money market mutual funds $ 50,427 $ — $ — $ 50,427 $ 45,439 $ 4,988 Total cash equivalents $ 50,427 $ — $ — $ 50,427 $ 45,439 $ 4,988 U.S. government and agency bonds $ 103,776 $ 69 $ (67 ) $ 103,778 $ 69,779 $ 33,999 Corporate bonds 76,256 162 (13 ) 76,405 — 76,405 Certificates of deposit 9,688 13 (3 ) 9,698 — 9,698 Total short-term investments $ 189,720 $ 244 $ (83 ) $ 189,881 $ 69,779 $ 120,102 U.S. government and agency bonds $ 57,647 $ 294 $ (3 ) $ 57,938 $ 29,915 $ 28,023 Corporate bonds 814 44 (40 ) 818 — 818 Certificates of deposit 3,904 17 — 3,921 — 3,921 Total long-term investments $ 62,365 $ 355 $ (43 ) $ 62,677 $ 29,915 $ 32,762 December 31, 2018 Money market mutual funds $ 47,199 $ — $ — $ 47,199 $ 47,199 $ — Total cash equivalents $ 47,199 $ — $ — $ 47,199 $ 47,199 $ — U.S. government and agency bonds $ 112,995 $ — $ (486 ) $ 112,509 $ 69,605 $ 42,904 Corporate bonds 56,235 — (210 ) 56,025 — 56,025 Certificates of deposit 6,506 — — 6,506 — 6,506 Total short-term investments $ 175,736 $ — $ (696 ) $ 175,040 $ 69,605 $ 105,435 U.S. government and agency bonds $ 90,458 $ 99 $ (155 ) $ 90,402 $ 64,086 $ 26,316 Corporate bonds 46,743 43 (68 ) 46,718 — 46,718 Certificates of deposit 3,664 — — 3,664 — 3,664 Total long-term investments $ 140,865 $ 142 $ (223 ) $ 140,784 $ 64,086 $ 76,698

Convertible Debt, Net

Convertible Debt, Net	6 Months Ended
	Jun. 30, 2019
Debt Disclosure [Abstract]
Convertible Debt, Net	Convertible Debt, Net The Company had outstanding convertible debt and related debt issuance costs on its consolidated balance sheet as follows: As of (in thousands) June 30, 2019 December 31, 2018 1.25% Convertible Senior Notes, due September 2021 $ 344,992 $ 344,992 1.375% Convertible Senior Notes, due November 2024 402,500 402,500 Unamortized debt discount (129,616 ) (143,616 ) Debt issuance costs (10,525 ) (11,898 ) Total convertible debt, net $ 607,351 $ 591,978 The carrying amount and the estimated fair value of the Company's convertible debt, which is based on the Level 2 quoted market prices as of June 30, 2019 and December 31, 2018 were as follows: As of June 30, 2019 December 31, 2018 (in thousands) Carrying Value Estimated Fair Value Carrying Value Estimated Fair Value 1.25% Convertible Senior Notes, due September 2021 $ 308,574 $ 693,455 $ 301,006 $ 483,851 1.375% Convertible Senior Notes, due November 2024 298,777 512,797 290,972 426,026 Total $ 607,351 $ 1,206,252 $ 591,978 $ 909,877

Net Income (Loss) Per Share

Net Income (Loss) Per Share	6 Months Ended
	Jun. 30, 2019
Disclosure Potential Common Shares Excluded From Computation Of Diluted Net Loss Per Share [Abstract]
Net Income (Loss) Per Share	Net Income (Loss) Per Share Basic net income (loss) per share is computed by dividing net income (loss) by the weighted average number of common shares outstanding for the period, excluding unvested restricted common shares. Diluted net income (loss) per share is computed using the weighted average number of common shares outstanding and, when dilutive, potential common share equivalents from outstanding stock options and restricted stock units (using the treasury-stock method), and potential common shares from the Company's convertible debt (using the if-converted method). The table below sets forth the components used in the computation of basic and diluted net income (loss) per share for the three and six months ended June 30, 2019 . Because the Company reported a net loss for the three and six months ended June 30, 2018 , all potential dilutive common shares have been excluded from the computation of the diluted net loss per share for three and six months ended June 30, 2018 , as the effect would have been anti-dilutive. June 30, 2019 (in thousands, except share and per share data) Three Months Ended Six Months Ended Numerator: Net income $ 1,402 $ 5,780 Denominator: Basic weighted average common shares outstanding 59,844,991 59,601,365 Effect of dilutive securities Stock options 1,479,713 1,513,886 Restricted stock units 161,621 217,200 Convertible debt — — Diluted shares 61,486,325 61,332,451 Net income per share: Basic $ 0.02 $ 0.10 Diluted $ 0.02 $ 0.09 For the three and six months ended June 30, 2019 , certain potential outstanding shares from stock options, restricted stock units and convertible debt were excluded from the computation of diluted net income per share because the effect of including these items was anti-dilutive. Additionally, certain performance-based restricted stock units were excluded from the computation of diluted net income per share because the underlying performance conditions for such restricted stock units had not yet been met. The number of potential common share equivalents excluded from the computation of diluted net income (loss) per share for the three and six months ended June 30, 2019 and 2018 are as follows: June 30, 2019 June 30, 2018 Three Months Ended Six Months Ended Three and Six Months Ended 1.25% Convertible Senior Notes 5,910,954 5,910,954 5,910,954 1.375% Convertible Senior Notes 4,319,429 4,319,429 4,319,429 Unvested restricted stock units 426,550 421,776 914,710 Stock options 181,132 231,289 3,199,238 Total 10,838,065 10,883,448 14,344,331

Inventories

Inventories	6 Months Ended
	Jun. 30, 2019
Inventory Disclosure [Abstract]
Inventories	Inventories At the end of each period, inventories were comprised of the following: As of (in thousands) June 30, 2019 December 31, 2018 Raw materials $ 17,960 $ 10,347 Work-in-process 26,979 30,222 Finished goods 40,170 30,845 Total inventories $ 85,109 $ 71,414

Goodwill and Other Intangible A

Goodwill and Other Intangible Assets, Net	6 Months Ended
	Jun. 30, 2019
Goodwill and Intangible Assets Disclosure [Abstract]
Goodwill and Other Intangible Assets, Net	oodwill and Other Intangible Assets, Net The changes in the carrying amounts of goodwill for the six months ended June 30, 2019 were as follows: (in thousands) Goodwill at December 31, 2018 $ 39,646 Foreign currency translation 93 Goodwill at June 30, 2019 $ 39,739 The gross carrying amount, accumulated amortization and net book value of intangible assets at the end of each period were as follows: As of June 30, 2019 December 31, 2018 (in thousands) Gross Carrying Amount Accumulated Amortization Net Book Value Gross Carrying Amount Accumulated Amortization Net Book Value Customer and contractual relationships $ 9,850 $ (2,326 ) $ 7,524 $ 6,109 $ (1,880 ) $ 4,229 Internal-use software 10,581 (5,940 ) 4,641 11,262 (5,108 ) 6,154 Intellectual property 875 — 875 — — — Total $ 21,306 $ (8,266 ) $ 13,040 $ 17,371 $ (6,988 ) $ 10,383 Amortization expense for intangible assets was $0.6 million and $0.4 million for the three months ended June 30, 2019 and 2018 , respectively. Amortization expense for intangible assets was $1.2 million and $0.8 million for the six months ended June 30, 2019 and 2018 , respectively. Estimated future amortization expense by year is as follows: Years Ending December 31, (in thousands) 2019 (remaining) $ 1,405 2020 2,547 2021 2,043 2022 1,460 2023 1,021 Thereafter 4,564 Total $ 13,040

Accrued Expenses and Other Curr

Accrued Expenses and Other Current Liabilities	6 Months Ended
	Jun. 30, 2019
Payables and Accruals [Abstract]
Accrued Expenses and Other Current Liabilities	ccrued Expenses and Other Current Liabilities The components of accrued expenses and other current liabilities were as follows: As of (in thousands) June 30, 2019 December 31, 2018 Employee compensation and related costs $ 34,348 $ 37,822 Professional and consulting services 12,856 14,925 Supplier purchases 3,089 7,742 Value added taxes payable 3,527 8,463 Other 27,201 21,205 Accrued expenses and other current liabilities $ 81,021 $ 90,157 Product Warranty Costs The Company provides a four -year warranty on Personal Diabetes Managers (“PDMs”) sold in the United States and Europe and a five -year warranty on PDMs sold in Canada and may replace Pods that do not function in accordance with product specifications. The Company estimates its warranty at the time the product is shipped based on historical experience and the estimated cost to service the claims. Since the Company continues to introduce new products and versions, the anticipated performance of the product over the warranty period is also considered in estimating warranty reserves. Warranty expense is recorded in cost of goods sold in the consolidated statements of operations. Cost to service the claims reflects the current product cost. A reconciliation of the changes in the Company’s product warranty liability is as follows: Three Months Ended June 30, Six Months Ended June 30, (in thousands) 2019 2018 2019 2018 Product warranty liability at beginning of period $ 6,283 $ 5,386 $ 6,379 $ 5,337 Warranty expense 3,147 1,529 5,366 3,501 Warranty claims settled (2,791 ) (1,412 ) (5,106 ) (3,335 ) Product warranty liability at end of period $ 6,639 $ 5,503 $ 6,639 $ 5,503 Product warranty liability was included in the following consolidated balance sheet accounts in the amounts shown: As of (in thousands) June 30, 2019 December 31, 2018 Accrued expenses and other current liabilities $ 2,906 $ 2,701 Other liabilities 3,733 3,678 Total $ 6,639 $ 6,379

Commitments and Contingencies

Commitments and Contingencies	6 Months Ended
	Jun. 30, 2019
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	ommitments and Contingencies Legal Proceedings Between May 5, 2015 and June 16, 2015, three class action lawsuits were filed by shareholders in the U.S. District Court, for the District of Massachusetts, against the Company and certain individual and former executives of the Company. Two suits subsequently were voluntarily dismissed. Arkansas Teacher Retirement System v. Insulet, et al., 1:15-cv-12345, (“ATRS”) alleged that the Company (and certain executives) committed violations of Sections 10(b) and 20(a) and Rule 10b-5 of the Securities Exchange Act of 1934 by making allegedly false and misleading statements about the Company’s business, operations, and prospects. On February 8, 2018, the parties executed a binding stipulation of settlement, under which all claims were released and a payment was made into an escrow account for the plaintiffs and the class they purport to represent. On August 6, 2018, the Court issued an order approving the settlement. The Company had previously accrued fees and expenses in connection with this matter for the amount of the final settlement liability that was not covered by insurance, the amount of which was not material to the Company's consolidated financial statements. In addition, on April 26, 2017, a derivative action (Walker v. DeSisto, et al., 1:17-cv-10738) (“Walker”) was filed, and on October 13, 2017, a second derivative action (Carnazza v. DeSisto, et al., 1:17-cv-11977) (“Carnazza”) was filed, both on behalf of the Company, each by a shareholder in the U.S. District Court for the District of Massachusetts against the Company (as a nominal defendant) and certain individual current and former officers and directors of the Company. The allegations in the actions are substantially similar to those alleged in the securities class action. The actions seek, among other things, damages, disgorgement of certain types of compensation or profits, and attorneys’ fees and costs. On July 11, 2018, the parties executed a binding stipulation of settlement, under which all claims were released and a payment of attorneys’ fees and reimbursement of expenses will be paid to plaintiffs’ counsel, subject to the Court’s approval. On July 13, 2018, the plaintiffs filed a motion for preliminary approval of the settlement, which is pending. The Company expects that such fees and expenses payable to plaintiff's counsel will be covered by the Company's insurance. The Company is, from time to time, involved in the normal course of business in various legal proceedings, including intellectual property, contract, employment and product liability suits. Although the Company is unable to quantify the exact financial impact of any of these matters, the Company believes that none of these currently pending matters will have an outcome material to its financial condition or business. Fees To Former European Distributor Following the expiration of an agreement with a former European distributor on June 30, 2018, the Company was required to pay a quarterly per-unit fee for Omnipod sales to certain customers of the former European distributor for a one-year period through June 30, 2019. The Company recognized a liability and an associated intangible asset for this fee as qualifying sales occurred. The methodology applicable for determining the total fee under under the distribution agreement is subject to an active arbitration proceeding in Switzerland. The final amount of the fee could vary significantly depending on the number of customers who count for purposes of calculating the fee under the terms of the agreement. The Company estimates that the final aggregate fee is in the range of $5 million to $55 million . As of June 30, 2019, the Company had recognized $7.8 million

Leases

Leases	6 Months Ended
	Jun. 30, 2019
Leases [Abstract]
Leases	Leases As discussed in Note 2, ASC 842 requires lessees to recognize ROU assets and lease liabilities on the balance sheet for those leases classified as operating leases. In accordance with ASC 842, the Company determines if an arrangement is a lease at inception. Operating lease ROU assets and operating lease liabilities are recognized based on the present value of the future minimum lease payments over the lease term at commencement date. The Company uses its incremental borrowing rate in determining the present value of future payments since most of its leases do not provide an implicit interest rate. The operating lease ROU asset also includes any lease payments made and excludes lease incentives and initial direct costs incurred. On January 1, 2019, upon the adoption of ASC 842, the Company recorded ROU assets of $8.8 million and operating lease liabilities of $10.8 million on its consolidated balance sheet. The difference between the approximate value of the ROU assets and the approximate value of the lease obligations is primarily attributable to a former cease-use liability. The Company's lease terms may include options to extend or terminate the lease when it is reasonably certain that the Company will exercise that option. Lease expense for minimum lease payments is recognized on a straight-line basis over the lease term. The Company leases approximately 100,000 square feet of laboratory and office space in Billerica, Massachusetts. The lease expires in November 2022 and contains escalating payments over its life. Additionally, the Company leases approximately 29,000 square feet of warehousing space in Billerica, Massachusetts under a lease expiring in September 2019. The Company also leases international and certain other U.S. facilities. These operating leases expire at various dates through 2026, some of which may include options to extend the leases for up to 5 years , and some of which may include options to terminate the leases at certain times within the lease term. In the normal course of business, it is expected that these leases will be renewed. The Company's total operating lease cost, which is recorded in general and administrative expenses in the consolidated statements of operations, was $0.9 million and $1.8 million for the three and six months ended June 30, 2019 , respectively. Cash paid for amounts included in the measurement of lease liabilities was $0.8 million and $1.6 million for three and six months ended June 30, 2019 , respectively. The future minimum undiscounted lease payments under operating leases as of June 30, 2019 are as follows: Years Ending December 31, (in thousands) 2019 (remaining) $ 1,659 2020 2,955 2021 2,899 2022 2,575 2023 269 Thereafter 561 Total future minimum lease payments 10,918 Less: imputed interest (1,089 ) Present value of future minimum lease payments $ 9,829 As of June 30, 2019, ROU assets and operating lease liabilities were included in the following consolidated balance sheet accounts in the amounts shown: As of June 30, 2019 (in thousands) ROU asset: Other assets $ 8,020 Operating lease liabilities: Accrued expenses and other current liabilities $ 2,333 Other liabilities 7,496 Total $ 9,829 As of June 30, 2019 , the weighted average remaining lease term for operating leases was 3.7 years and the weighted-average discount rate used to determine the operating lease liability was 6.7% .

Stock-Based Compensation

Stock-Based Compensation	6 Months Ended
	Jun. 30, 2019
Share-based Payment Arrangement [Abstract]
Stock-Based Compensation	tock-Based Compensation The following table reflects the Company's stock-based compensation expense related to share-based awards for the three and six months ended June 30, 2019 and 2018 : Three Months Ended June 30, Six Months Ended June 30, Unamortized Expense Weighted Average Remaining Expense Period (Years) ($ in thousands) 2019 2018 2019 2018 At June 30, 2019 Stock options $ 1,583 $ 2,272 $ 3,223 $ 4,630 $ 10,906 2.7 Restricted stock units 6,393 4,371 10,137 9,899 39,369 2.2 Employee stock purchase plan 318 294 718 588 739 0.4 Total $ 8,294 $ 6,937 $ 14,078 $ 15,117 $ 51,014 The following summarizes stock option activity for the six months ended June 30, 2019 : Number of Options Weighted Average Exercise Price Aggregate Intrinsic Value (in thousands) Weighted Average Remaining Contractual Term (years) Outstanding at December 31, 2018 3,077,624 $ 39.16 Granted 125,640 93.16 Exercised (721,041 ) 33.42 $ 49,242 Forfeited / Expired (111,604 ) 48.06 Outstanding at June 30, 2019 2,370,619 $ 43.35 $ 180,231 5.3 Vested, June 30, 2019 1,839,054 $ 37.50 $ 150,573 4.5 Vested or expected to vest, June 30, 2019 (1) 2,309,525 $ 177,471 (1) Represents total outstanding stock options as of June 30, 2019 , adjusted for estimated forfeitures. The following table summarizes activity for the Company’s restricted stock units during the six months ended June 30, 2019 : Number of Shares Weighted Average Fair Value Outstanding at December 31, 2018 752,207 $ 55.02 Granted 311,950 93.79 Vested (307,217 ) 45.36 Forfeited (51,645 ) 63.77 Outstanding at June 30, 2019 705,295 $ 75.73

Interest Expense

Interest Expense	6 Months Ended
	Jun. 30, 2019
Other Income and Expenses [Abstract]
Interest Expense	Interest Expense Interest expense, net of portion capitalized was as follows: Three Months Ended June 30, Six Months Ended June 30, (in thousands) 2019 2018 2019 2018 Contractual coupon interest $ 2,462 $ 2,462 $ 4,924 $ 4,942 Accretion of debt discount 7,057 6,616 14,000 13,138 Amortization of debt issuance costs 692 648 1,372 1,289 Capitalized interest (2,569 ) (2,436 ) (6,039 ) (4,161 ) Interest expense, net of portion capitalized $ 7,642 $ 7,290 $ 14,257 $ 15,208 Interest expense related to convertible debt for the three and six months ended June 30, 2019 was as follows: Three Months Ended June 30, 2019 Six Months Ended June 30, 2019 (in thousands) 1.375% 1.25% 2.0% Total 1.375% 1.25% 2.0% Total Contractual coupon interest $ 1,384 $ 1,078 $ — $ 2,462 $ 2,768 $ 2,156 $ — $ 4,924 Amortization of debt discount and issuance costs 3,924 3,825 — 7,749 7,803 7,569 — 15,372 Total $ 5,308 $ 4,903 $ — $ 10,211 $ 10,571 $ 9,725 $ — $ 20,296 Interest expense related to convertible debt for the three and six months ended June 30, 2018 is as follows: Three Months Ended June 30, 2018 Six Months Ended June 30, 2018 (in thousands) 1.375% 1.25% 2.0% Total 1.375% 1.25% 2.0% Total Contractual coupon interest $ 1,383 $ 1,078 $ 1 $ 2,462 $ 2,767 $ 2,156 $ 19 $ 4,942 Amortization of debt discount and issuance costs 3,654 3,589 21 7,264 7,265 7,102 60 14,427 Total $ 5,037 $ 4,667 $ 22 $ 9,726 $ 10,032 $ 9,258 $ 79 $ 19,369

Income Tax Expense

Income Tax Expense	6 Months Ended
	Jun. 30, 2019
Income Tax Disclosure [Abstract]
Income Tax Expense	Income Tax Expense The Company's effective tax rate for the three and six months ended June 30, 2019 was a positive rate of 25.6% and 12.3% , compared with a negative rate of 32.2% and 9.9% for the same periods of 2018. The negative effective tax rate in the 2018 periods resulted from recording state income and foreign taxes in jurisdictions with taxable income, mainly the United Kingdom and Canada. Income tax benefits have not been recorded for losses in jurisdictions where valuation allowances exist against net deferred tax assets; primarily in the United States. As of June 30, 2019 and December 31, 2018, the Company maintained a full valuation allowance against its U.S. net deferred tax assets based on the determination that it is not more likely than not these future benefits will be realized before expiration.

Basis of Presentation (Policies

Basis of Presentation (Policies)	6 Months Ended
	Jun. 30, 2019
Accounting Policies [Abstract]
Basis of Presentation	Basis of Presentation The accompanying financial statements reflect the consolidated operations of Insulet and its subsidiaries (the “Company”). The unaudited consolidated financial statements have been prepared in accordance with generally accepted accounting principles in the United States of America (“U.S. GAAP”). The preparation of financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions in the application of certain of its significant accounting policies that may materially affect the reported amounts of assets, liabilities, equity, revenue and expenses. Actual results may differ from those estimates. In management's opinion, the unaudited consolidated financial statements contain all normal recurring adjustments necessary for a fair statement of the interim results reported. Operating results for the three and six months ended June 30, 2019 are not necessarily indicative of the results that may be expected for the full year ending December 31, 2019 , or for any other subsequent interim period. The year-end balance sheet data was derived from audited consolidated financial statements. These consolidated financial statements do not include all of the annual disclosures required by U.S. GAAP; accordingly, they should be read in conjunction with the Company’s audited consolidated financial statements contained in the Company’s Annual Report on Form 10-K for the year ended December 31, 2018 .
Reclassification of Prior Period Amounts	Reclassification of Prior Period Amounts
Recently Adopted and Not Yet Adopted Accounting Pronouncements	Recently Adopted Accounting Standards Effective January 1, 2019, the Company adopted Accounting Standards Update (“ASU”) No. 2016-02, Leases (Topic 842) (“ASU 2016-02”). ASU 2016-02 and its related amendments (collectively referred to as ASC 842), which amends the guidance in former ASC Topic 840, Leases. The new standard requires lessees to recognize right-of-use (“ROU”) assets and lease liabilities on the balance sheet for those leases classified as operating leases. The Company adopted ASC 842 on January 1, 2019 using the modified retrospective method, whereby the new guidance is applied prospectively as of the date of adoption and prior periods are not restated. The Company elected the practical expedients that permit the Company to not reassess (1) whether any expired or existing contracts are or contain leases, (2) the lease classification for any expired or existing leases, and (3) any initial direct costs for any existing leases as of the effective date. The Company also excludes leases with an expected term of less than one year from the application of ASC 842. Adoption of the lease standard had a material impact on the Company's consolidated balance sheet, which is disclosed in Note 11 . Effective January 1, 2019, the Company early adopted ASU 2018-15, Customer's Accounting for Implementation Costs Incurred in a Cloud Computing Arrangement That Is a Service Contract (“ASU 2018-15”). ASU 2018-15 requires certain costs to implement a cloud computing arrangement that is a service contract to be capitalized consistent with the rules applicable to internal-use software capitalization projects. The Company adopted this new guidance effective January 1, 2019, prospectively. The Company defers eligible costs related to the implementation of cloud computing arrangements within other current and non-current assets and amortizes such costs over the expected term of the hosting arrangement to the same income statement line as the associated cloud operating expenses. Adoption of this standard resulted in the Company capitalizing $0.7 million and $2.0 million of cloud computing implementation costs for the three and six months ended June 30, 2019 , respectively.
Product Warranty Costs	Product Warranty Costs The Company provides a four -year warranty on Personal Diabetes Managers (“PDMs”) sold in the United States and Europe and a five

Revenue and Contract Acquisit_2

Revenue and Contract Acquisition Costs (Tables)	6 Months Ended
	Jun. 30, 2019
Revenue from Contract with Customer [Abstract]
Disaggregation of Revenue	The following table summarizes revenue from contracts with customers for the three and six months ended June 30, 2019 and 2018 : Three Months Ended June 30, Six Months Ended June 30, (in thousands) 2019 2018 2019 2018 U.S. Omnipod $ 98,074 $ 78,047 $ 184,177 $ 148,319 International Omnipod 62,736 28,509 119,624 66,913 Total Diabetes Revenue 160,810 106,556 303,801 215,232 Drug Delivery 16,326 17,706 32,890 32,608 Total $ 177,136 $ 124,262 $ 336,691 $ 247,840
Schedule of revenue from major customers	Revenue for customers comprising more than 10% of total revenue were as follows: Three Months Ended June 30, Six Months Ended June 30, 2019 2018 2019 2018 Amgen, Inc. * 14% 10% 13% Ypsomed * * * 17% Cardinal Health Inc. and affiliates 12% 13% 11% 12% * Represents less than 10% of consolidated revenue.
Summary of Deferred Revenue	Deferred revenue related to unsatisfied performance obligations was included in the following consolidated balance sheet accounts in the amounts shown: As of (in thousands) June 30, 2019 December 31, 2018 Accrued expenses and other current liabilities $ 1,374 $ 1,184 Other liabilities 986 931 Total deferred revenue $ 2,360 $ 2,115
Summary of Contract Acquisition Costs	Contract acquisition costs, representing capitalized commissions costs related to new patient starts, net of amortization, were included in the following consolidated balance sheet accounts in the amounts shown: As of (in thousands) June 30, 2019 December 31, 2018 Prepaid expenses and other current assets $ 8,452 $ 7,277 Other assets 18,183 15,988 Total capitalized contract acquisition costs, net $ 26,635 $ 23,265

Investments (Tables)

Investments (Tables)	6 Months Ended
	Jun. 30, 2019
Investments, Debt and Equity Securities [Abstract]
Schedule investments	The following table provides amortized cost, gross unrealized gains and losses, fair value and the level in the fair value hierarchy for the Company's investments as of June 30, 2019 and December 31, 2018: (in thousands) Amortized Cost Gross Unrealized Gains Gross Unrealized (Losses) Fair Value Level 1 Level 2 June 30, 2019 Money market mutual funds $ 50,427 $ — $ — $ 50,427 $ 45,439 $ 4,988 Total cash equivalents $ 50,427 $ — $ — $ 50,427 $ 45,439 $ 4,988 U.S. government and agency bonds $ 103,776 $ 69 $ (67 ) $ 103,778 $ 69,779 $ 33,999 Corporate bonds 76,256 162 (13 ) 76,405 — 76,405 Certificates of deposit 9,688 13 (3 ) 9,698 — 9,698 Total short-term investments $ 189,720 $ 244 $ (83 ) $ 189,881 $ 69,779 $ 120,102 U.S. government and agency bonds $ 57,647 $ 294 $ (3 ) $ 57,938 $ 29,915 $ 28,023 Corporate bonds 814 44 (40 ) 818 — 818 Certificates of deposit 3,904 17 — 3,921 — 3,921 Total long-term investments $ 62,365 $ 355 $ (43 ) $ 62,677 $ 29,915 $ 32,762 December 31, 2018 Money market mutual funds $ 47,199 $ — $ — $ 47,199 $ 47,199 $ — Total cash equivalents $ 47,199 $ — $ — $ 47,199 $ 47,199 $ — U.S. government and agency bonds $ 112,995 $ — $ (486 ) $ 112,509 $ 69,605 $ 42,904 Corporate bonds 56,235 — (210 ) 56,025 — 56,025 Certificates of deposit 6,506 — — 6,506 — 6,506 Total short-term investments $ 175,736 $ — $ (696 ) $ 175,040 $ 69,605 $ 105,435 U.S. government and agency bonds $ 90,458 $ 99 $ (155 ) $ 90,402 $ 64,086 $ 26,316 Corporate bonds 46,743 43 (68 ) 46,718 — 46,718 Certificates of deposit 3,664 — — 3,664 — 3,664 Total long-term investments $ 140,865 $ 142 $ (223 ) $ 140,784 $ 64,086 $ 76,698

Convertible Debt, Net (Tables)

Convertible Debt, Net (Tables)	6 Months Ended
	Jun. 30, 2019
Debt Disclosure [Abstract]
Outstanding Convertible Debt and Related Deferred Financing Costs	The Company had outstanding convertible debt and related debt issuance costs on its consolidated balance sheet as follows: As of (in thousands) June 30, 2019 December 31, 2018 1.25% Convertible Senior Notes, due September 2021 $ 344,992 $ 344,992 1.375% Convertible Senior Notes, due November 2024 402,500 402,500 Unamortized debt discount (129,616 ) (143,616 ) Debt issuance costs (10,525 ) (11,898 ) Total convertible debt, net $ 607,351 $ 591,978
Fair Value, Liabilities Measured on Recurring and Nonrecurring Basis	The carrying amount and the estimated fair value of the Company's convertible debt, which is based on the Level 2 quoted market prices as of June 30, 2019 and December 31, 2018 were as follows: As of June 30, 2019 December 31, 2018 (in thousands) Carrying Value Estimated Fair Value Carrying Value Estimated Fair Value 1.25% Convertible Senior Notes, due September 2021 $ 308,574 $ 693,455 $ 301,006 $ 483,851 1.375% Convertible Senior Notes, due November 2024 298,777 512,797 290,972 426,026 Total $ 607,351 $ 1,206,252 $ 591,978 $ 909,877

Net Income (Loss) Per Share (Ta

Net Income (Loss) Per Share (Tables)	6 Months Ended
	Jun. 30, 2019
Disclosure Potential Common Shares Excluded From Computation Of Diluted Net Loss Per Share [Abstract]
Schedule of Earnings Per Share, Basic and Diluted	The table below sets forth the components used in the computation of basic and diluted net income (loss) per share for the three and six months ended June 30, 2019 . Because the Company reported a net loss for the three and six months ended June 30, 2018 , all potential dilutive common shares have been excluded from the computation of the diluted net loss per share for three and six months ended June 30, 2018 , as the effect would have been anti-dilutive. June 30, 2019 (in thousands, except share and per share data) Three Months Ended Six Months Ended Numerator: Net income $ 1,402 $ 5,780 Denominator: Basic weighted average common shares outstanding 59,844,991 59,601,365 Effect of dilutive securities Stock options 1,479,713 1,513,886 Restricted stock units 161,621 217,200 Convertible debt — — Diluted shares 61,486,325 61,332,451 Net income per share: Basic $ 0.02 $ 0.10 Diluted $ 0.02 $ 0.09
Potential Common Shares Excluded from Computation of Diluted Net Loss per Share	The number of potential common share equivalents excluded from the computation of diluted net income (loss) per share for the three and six months ended June 30, 2019 and 2018 are as follows: June 30, 2019 June 30, 2018 Three Months Ended Six Months Ended Three and Six Months Ended 1.25% Convertible Senior Notes 5,910,954 5,910,954 5,910,954 1.375% Convertible Senior Notes 4,319,429 4,319,429 4,319,429 Unvested restricted stock units 426,550 421,776 914,710 Stock options 181,132 231,289 3,199,238 Total 10,838,065 10,883,448 14,344,331

Inventories (Tables)

Inventories (Tables)	6 Months Ended
	Jun. 30, 2019
Inventory Disclosure [Abstract]
Components of Inventories	At the end of each period, inventories were comprised of the following: As of (in thousands) June 30, 2019 December 31, 2018 Raw materials $ 17,960 $ 10,347 Work-in-process 26,979 30,222 Finished goods 40,170 30,845 Total inventories $ 85,109 $ 71,414

Goodwill and Other Intangible_2

Goodwill and Other Intangible Assets, Net (Tables)	6 Months Ended
	Jun. 30, 2019
Goodwill and Intangible Assets Disclosure [Abstract]
Summary of Changes in Carrying Amounts of Goodwill	The changes in the carrying amounts of goodwill for the six months ended June 30, 2019 were as follows: (in thousands) Goodwill at December 31, 2018 $ 39,646 Foreign currency translation 93 Goodwill at June 30, 2019 $ 39,739
Components of Other Intangible Assets	The gross carrying amount, accumulated amortization and net book value of intangible assets at the end of each period were as follows: As of June 30, 2019 December 31, 2018 (in thousands) Gross Carrying Amount Accumulated Amortization Net Book Value Gross Carrying Amount Accumulated Amortization Net Book Value Customer and contractual relationships $ 9,850 $ (2,326 ) $ 7,524 $ 6,109 $ (1,880 ) $ 4,229 Internal-use software 10,581 (5,940 ) 4,641 11,262 (5,108 ) 6,154 Intellectual property 875 — 875 — — — Total $ 21,306 $ (8,266 ) $ 13,040 $ 17,371 $ (6,988 ) $ 10,383
Amortization Expense Expected for Next Five Years	Estimated future amortization expense by year is as follows: Years Ending December 31, (in thousands) 2019 (remaining) $ 1,405 2020 2,547 2021 2,043 2022 1,460 2023 1,021 Thereafter 4,564 Total $ 13,040

Accrued Expenses and Other Cu_2

Accrued Expenses and Other Current Liabilities (Tables)	6 Months Ended
	Jun. 30, 2019
Payables and Accruals [Abstract]
Components of accrued expenses and other current liabilities	The components of accrued expenses and other current liabilities were as follows: As of (in thousands) June 30, 2019 December 31, 2018 Employee compensation and related costs $ 34,348 $ 37,822 Professional and consulting services 12,856 14,925 Supplier purchases 3,089 7,742 Value added taxes payable 3,527 8,463 Other 27,201 21,205 Accrued expenses and other current liabilities $ 81,021 $ 90,157
Reconciliation of Changes in Product Warranty Liability	A reconciliation of the changes in the Company’s product warranty liability is as follows: Three Months Ended June 30, Six Months Ended June 30, (in thousands) 2019 2018 2019 2018 Product warranty liability at beginning of period $ 6,283 $ 5,386 $ 6,379 $ 5,337 Warranty expense 3,147 1,529 5,366 3,501 Warranty claims settled (2,791 ) (1,412 ) (5,106 ) (3,335 ) Product warranty liability at end of period $ 6,639 $ 5,503 $ 6,639 $ 5,503 Product warranty liability was included in the following consolidated balance sheet accounts in the amounts shown: As of (in thousands) June 30, 2019 December 31, 2018 Accrued expenses and other current liabilities $ 2,906 $ 2,701 Other liabilities 3,733 3,678 Total $ 6,639 $ 6,379

Leases (Tables)

Leases (Tables)	6 Months Ended
	Jun. 30, 2019
Leases [Abstract]
Future Minimum Undiscounted Lease Payments	The future minimum undiscounted lease payments under operating leases as of June 30, 2019 are as follows: Years Ending December 31, (in thousands) 2019 (remaining) $ 1,659 2020 2,955 2021 2,899 2022 2,575 2023 269 Thereafter 561 Total future minimum lease payments 10,918 Less: imputed interest (1,089 ) Present value of future minimum lease payments $ 9,829
Summary of ROU Assets and Operating Lease Liabilities	As of June 30, 2019, ROU assets and operating lease liabilities were included in the following consolidated balance sheet accounts in the amounts shown: As of June 30, 2019 (in thousands) ROU asset: Other assets $ 8,020 Operating lease liabilities: Accrued expenses and other current liabilities $ 2,333 Other liabilities 7,496 Total $ 9,829

Stock-Based Compensation (Table

Stock-Based Compensation (Tables)	6 Months Ended
	Jun. 30, 2019
Share-based Payment Arrangement [Abstract]
Stock option activity	The following table reflects the Company's stock-based compensation expense related to share-based awards for the three and six months ended June 30, 2019 and 2018 : Three Months Ended June 30, Six Months Ended June 30, Unamortized Expense Weighted Average Remaining Expense Period (Years) ($ in thousands) 2019 2018 2019 2018 At June 30, 2019 Stock options $ 1,583 $ 2,272 $ 3,223 $ 4,630 $ 10,906 2.7 Restricted stock units 6,393 4,371 10,137 9,899 39,369 2.2 Employee stock purchase plan 318 294 718 588 739 0.4 Total $ 8,294 $ 6,937 $ 14,078 $ 15,117 $ 51,014 The following summarizes stock option activity for the six months ended June 30, 2019 : Number of Options Weighted Average Exercise Price Aggregate Intrinsic Value (in thousands) Weighted Average Remaining Contractual Term (years) Outstanding at December 31, 2018 3,077,624 $ 39.16 Granted 125,640 93.16 Exercised (721,041 ) 33.42 $ 49,242 Forfeited / Expired (111,604 ) 48.06 Outstanding at June 30, 2019 2,370,619 $ 43.35 $ 180,231 5.3 Vested, June 30, 2019 1,839,054 $ 37.50 $ 150,573 4.5 Vested or expected to vest, June 30, 2019 (1) 2,309,525 $ 177,471 (1) Represents total outstanding stock options as of June 30, 2019 , adjusted for estimated forfeitures.
Summary of restricted stock units	The following table summarizes activity for the Company’s restricted stock units during the six months ended June 30, 2019 : Number of Shares Weighted Average Fair Value Outstanding at December 31, 2018 752,207 $ 55.02 Granted 311,950 93.79 Vested (307,217 ) 45.36 Forfeited (51,645 ) 63.77 Outstanding at June 30, 2019 705,295 $ 75.73

Interest Expense (Tables)

Interest Expense (Tables)	6 Months Ended
	Jun. 30, 2019
Other Income and Expenses [Abstract]
Interest and Other Expense	Interest expense, net of portion capitalized was as follows: Three Months Ended June 30, Six Months Ended June 30, (in thousands) 2019 2018 2019 2018 Contractual coupon interest $ 2,462 $ 2,462 $ 4,924 $ 4,942 Accretion of debt discount 7,057 6,616 14,000 13,138 Amortization of debt issuance costs 692 648 1,372 1,289 Capitalized interest (2,569 ) (2,436 ) (6,039 ) (4,161 ) Interest expense, net of portion capitalized $ 7,642 $ 7,290 $ 14,257 $ 15,208 Interest expense related to convertible debt for the three and six months ended June 30, 2019 was as follows: Three Months Ended June 30, 2019 Six Months Ended June 30, 2019 (in thousands) 1.375% 1.25% 2.0% Total 1.375% 1.25% 2.0% Total Contractual coupon interest $ 1,384 $ 1,078 $ — $ 2,462 $ 2,768 $ 2,156 $ — $ 4,924 Amortization of debt discount and issuance costs 3,924 3,825 — 7,749 7,803 7,569 — 15,372 Total $ 5,308 $ 4,903 $ — $ 10,211 $ 10,571 $ 9,725 $ — $ 20,296 Interest expense related to convertible debt for the three and six months ended June 30, 2018 is as follows: Three Months Ended June 30, 2018 Six Months Ended June 30, 2018 (in thousands) 1.375% 1.25% 2.0% Total 1.375% 1.25% 2.0% Total Contractual coupon interest $ 1,383 $ 1,078 $ 1 $ 2,462 $ 2,767 $ 2,156 $ 19 $ 4,942 Amortization of debt discount and issuance costs 3,654 3,589 21 7,264 7,265 7,102 60 14,427 Total $ 5,037 $ 4,667 $ 22 $ 9,726 $ 10,032 $ 9,258 $ 79 $ 19,369

Basis of Presentation (Details)

Basis of Presentation (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Significant Accounting Policies [Line Items]
Cost of revenue	$ 60,718	$ 42,190	$ 113,577	$ 89,953
Shipping and Handling
Significant Accounting Policies [Line Items]
Cost of revenue	2,300	$ 1,400	4,900	$ 2,500
Accounting Standards Update 2018-15
Significant Accounting Policies [Line Items]
Hosting Arrangement, Service Contract, Implementation Cost, Capitalized	$ 700		$ 2,000

Revenue and Contract Acquisit_3

Revenue and Contract Acquisition Costs - Summary of Revenue from Contracts with Customers (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Disaggregation of Revenue [Line Items]
Revenue	$ 177,136	$ 124,262	$ 336,691	$ 247,840
U.S. Omnipod
Disaggregation of Revenue [Line Items]
Revenue	98,074	78,047	184,177	148,319
International Omnipod
Disaggregation of Revenue [Line Items]
Revenue	62,736	28,509	119,624	66,913
Diabetes
Disaggregation of Revenue [Line Items]
Revenue	160,810	106,556	303,801	215,232
Drug Delivery
Disaggregation of Revenue [Line Items]
Revenue	$ 16,326	$ 17,706	$ 32,890	$ 32,608

Revenue and Contract Acquisit_4

Revenue and Contract Acquisition Costs - Summary of Revenue from Customers - Concentration Risk (Details) - Customer concentration risk - Sales revenue	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Amgen, Inc.
Significant Accounting Policies [Line Items]
Total revenue, percentage		14.00%	10.00%	13.00%
Ypsomed
Significant Accounting Policies [Line Items]
Total revenue, percentage				17.00%
Cardinal Health Inc.
Significant Accounting Policies [Line Items]
Total revenue, percentage	12.00%	13.00%	11.00%	12.00%

Revenue and Contract Acquisit_5

Revenue and Contract Acquisition Costs - Summary of Deferred Revenue (Details) - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018
Revenue from Contract with Customer [Abstract]
Accrued expenses and other current liabilities	$ 1,374	$ 1,184
Other liabilities	986	931
Total deferred revenue	$ 2,360	$ 2,115

Revenue and Contract Acquisit_6

Revenue and Contract Acquisition Costs - Narrative (Details) - USD ($)	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Revenue from Contract with Customer [Abstract]
Revenue recognized	$ 200,000	$ 1,100,000	$ 1,100,000	$ 2,400,000
Revenue recognized from performance obligations satisfied in previous periods	0	$ 0	0	$ 0
Amortization of capitalized commission costs	$ 2,100,000		$ 4,100,000

Revenue and Contract Acquisit_7

Revenue and Contract Acquisition Costs - Summary of Contract Acquisition Costs (Details) - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018
Revenue from Contract with Customer [Abstract]
Prepaid expenses and other current assets	$ 8,452	$ 7,277
Other assets	18,183	15,988
Total capitalized contract acquisition costs, net	$ 26,635	$ 23,265

Investments - Narrative (Detail

Investments - Narrative (Details) $ in Millions	3 Months Ended
	Jun. 30, 2019USD ($)security	Dec. 31, 2018USD ($)
Debt Securities, Available-for-sale [Line Items]
Restricted cash and cash equivalents | $	$ 2.7	$ 2.7
Number of positions | security	40
Minimum
Debt Securities, Available-for-sale [Line Items]
Derivative maturity date range	8 days
Maximum
Debt Securities, Available-for-sale [Line Items]
Derivative maturity date range	23 months

Investments - Schedule of Asset

Investments - Schedule of Assets Measured on a Recurring and Nonrecurring Basis (Details) - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018
Recurring fair value measurements:
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash equivalents	$ 50,427	$ 47,199
Recurring fair value measurements: | Money market mutual funds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash equivalents	50,427	47,199
Level 1 | Recurring fair value measurements:
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash equivalents	45,439	47,199
Level 1 | Recurring fair value measurements: | Money market mutual funds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash equivalents	45,439	47,199
Level 2 | Recurring fair value measurements:
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash equivalents	4,988	0
Level 2 | Recurring fair value measurements: | Money market mutual funds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash equivalents	4,988	0
Short-term investments
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Amortized Cost	189,720	175,736
Gross Unrealized Gains	244	0
Gross Unrealized (Losses)	(83)	(696)
Short-term investments | Recurring fair value measurements:
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	189,881	175,040
Short-term investments | Level 1 | Recurring fair value measurements:
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	69,779	69,605
Short-term investments | Level 1 | Recurring fair value measurements: | U.S. government and agency bonds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	69,779	69,605
Short-term investments | Level 1 | Recurring fair value measurements: | Corporate bonds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	0	0
Short-term investments | Level 1 | Recurring fair value measurements: | Certificates of deposit
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	0	0
Short-term investments | Level 2 | Recurring fair value measurements:
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	120,102	105,435
Short-term investments | Level 2 | Recurring fair value measurements: | U.S. government and agency bonds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	33,999	42,904
Short-term investments | Level 2 | Recurring fair value measurements: | Corporate bonds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	76,405	56,025
Short-term investments | Level 2 | Recurring fair value measurements: | Certificates of deposit
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	9,698	6,506
Short-term investments | U.S. government and agency bonds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Amortized Cost	103,776	112,995
Gross Unrealized Gains	69	0
Gross Unrealized (Losses)	(67)	(486)
Short-term investments | U.S. government and agency bonds | Recurring fair value measurements:
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	103,778	112,509
Short-term investments | Corporate bonds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Amortized Cost	76,256	56,235
Gross Unrealized Gains	162	0
Gross Unrealized (Losses)	(13)	(210)
Short-term investments | Corporate bonds | Recurring fair value measurements:
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	76,405	56,025
Short-term investments | Certificates of deposit
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Amortized Cost	9,688	6,506
Gross Unrealized Gains	13	0
Gross Unrealized (Losses)	(3)	0
Short-term investments | Certificates of deposit | Recurring fair value measurements:
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	9,698	6,506
Long-term investments
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Amortized Cost	62,365	140,865
Gross Unrealized Gains	355	142
Gross Unrealized (Losses)	(43)	(223)
Long-term investments | Recurring fair value measurements:
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	62,677	140,784
Long-term investments | Level 1 | Recurring fair value measurements:
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	29,915	64,086
Long-term investments | Level 1 | Recurring fair value measurements: | U.S. government and agency bonds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	29,915	64,086
Long-term investments | Level 1 | Recurring fair value measurements: | Corporate bonds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	0	0
Long-term investments | Level 1 | Recurring fair value measurements: | Certificates of deposit
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	0	0
Long-term investments | Level 2 | Recurring fair value measurements:
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	32,762	76,698
Long-term investments | Level 2 | Recurring fair value measurements: | U.S. government and agency bonds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	28,023	26,316
Long-term investments | Level 2 | Recurring fair value measurements: | Corporate bonds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	818	46,718
Long-term investments | Level 2 | Recurring fair value measurements: | Certificates of deposit
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	3,921	3,664
Long-term investments | U.S. government and agency bonds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Amortized Cost	57,647	90,458
Gross Unrealized Gains	294	99
Gross Unrealized (Losses)	(3)	(155)
Long-term investments | U.S. government and agency bonds | Recurring fair value measurements:
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	57,938	90,402
Long-term investments | Corporate bonds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Amortized Cost	814	46,743
Gross Unrealized Gains	44	43
Gross Unrealized (Losses)	(40)	(68)
Long-term investments | Corporate bonds | Recurring fair value measurements:
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	818	46,718
Long-term investments | Certificates of deposit
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Amortized Cost	3,904	3,664
Gross Unrealized Gains	17	0
Gross Unrealized (Losses)	0	0
Long-term investments | Certificates of deposit | Recurring fair value measurements:
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	$ 3,921	$ 3,664

Convertible Debt, Net - Outstan

Convertible Debt, Net - Outstanding Convertible Debt and Related Deferred Financing Costs (Details) - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018
Debt Instrument [Line Items]
Unamortized debt discount	$ (129,616)	$ (143,616)
Debt issuance costs	(10,525)	(11,898)
Total convertible debt, net	$ 607,351	$ 591,978
1.25% Convertible Notes
Debt Instrument [Line Items]
Debt, interest rate	1.25%	1.25%
1.375% Convertible Senior Notes
Debt Instrument [Line Items]
Debt, interest rate	1.375%	1.375%
Convertible Debt | 1.25% Convertible Notes
Debt Instrument [Line Items]
Principal amount of Senior Notes	$ 344,992	$ 344,992
Convertible Debt | 1.375% Convertible Senior Notes
Debt Instrument [Line Items]
Principal amount of Senior Notes	$ 402,500	$ 402,500

Convertible Debt, Net Convertib

Convertible Debt, Net Convertible Debt, Net - Summary of Convertible Debt (Details) - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018
1.25% Convertible Senior Notes
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt, interest rate	1.25%	1.25%
1.375% Convertible Senior Notes
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt, interest rate	1.375%	1.375%
Level 2 | Carrying Value
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial instrument value	$ 607,351	$ 591,978
Level 2 | Carrying Value | 1.25% Convertible Senior Notes
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial instrument value	308,574	301,006
Level 2 | Carrying Value | 1.375% Convertible Senior Notes
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial instrument value	298,777	290,972
Level 2 | Estimated Fair Value
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial instrument value	1,206,252	909,877
Level 2 | Estimated Fair Value | 1.25% Convertible Senior Notes
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial instrument value	693,455	483,851
Level 2 | Estimated Fair Value | 1.375% Convertible Senior Notes
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial instrument value	$ 512,797	$ 426,026

Net Income (Loss) Per Share - S

Net Income (Loss) Per Share - Schedule of Earnings per Share, Basic and Diluted (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Numerator:
Net income (loss)	$ 1,402	$ (1,691)	$ 5,780	$ (8,260)
Denominator:
Weighted average number of shares outstanding, basic (in shares)	59,844,991	58,833,498	59,601,365	58,659,111
Effect of dilutive securities
Weighted average number of shares outstanding, diluted (in shares)	61,486,325	58,833,498	61,332,451	58,659,111
Net income (loss) per share:
Net income (loss) per share: basic (in dollars per share)	$ 0.02	$ (0.03)	$ 0.10	$ (0.14)
Net income (loss) per shares: diluted (in dollars per share)	$ 0.02	$ (0.03)	$ 0.09	$ (0.14)
Stock options
Effect of dilutive securities
Effect of dilutive securities (in shares)	1,479,713		1,513,886
Stock options
Effect of dilutive securities
Effect of dilutive securities (in shares)	161,621		217,200
Convertible debt
Effect of dilutive securities
Effect of dilutive securities (in shares)	0		0

- Potential Common Shares Exclu

- Potential Common Shares Excluded from Computation of Diluted Net Loss Per Share (Detail) - shares	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Total dilutive common shares (in shares)	10,838,065	8,433,377	10,883,448	14,344,331
1.375% Convertible Senior Notes
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Total dilutive common shares (in shares)	4,319,429	4,319,429	4,319,429	4,319,429
1.25% Convertible Senior Notes
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Total dilutive common shares (in shares)	5,910,954	5,910,954	5,910,954	5,910,954
Unvested restricted stock units
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Total dilutive common shares (in shares)	426,550	914,710	421,776	914,710
Stock options
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Total dilutive common shares (in shares)	181,132	3,199,238	231,289	3,199,238

Inventories - Components of Inv

Inventories - Components of Inventories (Detail) - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018
Inventory Disclosure [Abstract]
Raw materials	$ 17,960	$ 10,347
Work-in-process	26,979	30,222
Finished goods	40,170	30,845
Total inventories	$ 85,109	$ 71,414

Goodwill and Other Intangible_3

Goodwill and Other Intangible Assets, Net - Summary of Changes in Carrying Amounts of Goodwill (Details) $ in Thousands	6 Months Ended
	Jun. 30, 2019USD ($)
Goodwill [Roll Forward]
Goodwill at December 31, 2018	$ 39,646
Foreign currency translation	93
Goodwill at June 30, 2019	$ 39,739

Goodwill and Other Intangible_4

Goodwill and Other Intangible Assets, Net - Narrative (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Goodwill and Intangible Assets Disclosure [Abstract]
Amortization of other intangible assets	$ 0.6	$ 0.4	$ 1.2	$ 0.8

Goodwill and Other Intangible_5

Goodwill and Other Intangible Assets, Net - Components of Other Intangible Assets (Details) - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018
Acquired Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	$ 21,306	$ 17,371
Accumulated Amortization	(8,266)	(6,988)
Net Book Value	13,040	10,383
Customer and Contractual Relationships
Acquired Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	9,850	6,109
Accumulated Amortization	(2,326)	(1,880)
Net Book Value	7,524	4,229
Internal-use software
Acquired Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	10,581	11,262
Accumulated Amortization	(5,940)	(5,108)
Net Book Value	4,641	6,154
Intellectual property
Acquired Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	875	0
Accumulated Amortization	0	0
Net Book Value	$ 875	$ 0

Goodwill and Other Intangible_6

Goodwill and Other Intangible Assets, Net - Amortization Expense Expected for Next Five Years (Details) $ in Thousands	Jun. 30, 2019USD ($)
Expected Amortization Expense [Line Items]
2019 (remaining)	$ 1,405
2020	2,547
2021	2,043
2022	1,460
2023	1,021
Thereafter	4,564
Net Book Value	$ 13,040

Accrued Expenses and Other Cu_3

Accrued Expenses and Other Current Liabilities - Summary of Accrued Expenses and Other Current Liabilities (Details) - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018
Payables and Accruals [Abstract]
Employee compensation and related costs	$ 34,348	$ 37,822
Professional and consulting services	12,856	14,925
Supplier purchases	3,089	7,742
Value added taxes payable	3,527	8,463
Accrued expenses and other current liabilities	2,906	2,701
Other	27,201	21,205
Accrued expenses and other current liabilities	$ 81,021	$ 90,157

Accrued Expenses and Other Cu_4

Accrued Expenses and Other Current Liabilities - Narrative (Details)	6 Months Ended
	Jun. 30, 2019
United States
Product Warranty Liability [Line Items]
Product warranty term for PDMs	4 years
CANADA
Product Warranty Liability [Line Items]
Product warranty term for PDMs	5 years

Accrued Expenses and Other Cu_5

Accrued Expenses and Other Current Liabilities - Product Warranty Liability (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Dec. 31, 2018
Movement in Standard and Extended Product Warranty Accrual, Increase (Decrease) [Roll Forward]
Product warranty liability at beginning of period	$ 6,283	$ 5,386	$ 6,379	$ 5,337
Warranty expense	3,147	1,529	5,366	3,501
Warranty claims settled	(2,791)	(1,412)	(5,106)	(3,335)
Product warranty liability at end of period	6,639	5,503	6,639	5,503
Composition of balance:
Accrued expenses and other current liabilities					$ 2,906	$ 2,701
Other liabilities					3,733	3,678
Total warranty balance	$ 6,283	$ 5,386	$ 6,379	$ 5,337	$ 6,639	$ 6,379

Commitments and Contingencies -

Commitments and Contingencies - Narrative (Details) $ in Millions	1 Months Ended
	Jun. 16, 2015lawsuit	Jun. 30, 2019USD ($)
Loss Contingencies [Line Items]
Number of class actions filed (in legal matters) | lawsuit	3
Number of class actions dismissed (in legal matters) | lawsuit	2
Fees To Former European Distributor | Minimum
Loss Contingencies [Line Items]
Commitment due in next twelve months		$ 5
Accrued liabilities		7.8
Fees To Former European Distributor | Maximum
Loss Contingencies [Line Items]
Commitment due in next twelve months		$ 55

Leases - Narrative (Details)

Leases - Narrative (Details) ft² in Thousands, $ in Thousands	3 Months Ended	6 Months Ended
	Jun. 30, 2019USD ($)ft²	Jun. 30, 2019USD ($)ft²	Jan. 01, 2019USD ($)
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Other assets	$ 8,020	$ 8,020
Operating lease liability	$ 9,829	$ 9,829
Option to extend lease, maximum number of years	5 years	5 years
Operating lease cost	$ 900	$ 1,800
Operating cash outflows from operating leases	$ 800	$ 1,600
Weighted average remaining lease term	3 years 8 months 12 days	3 years 8 months 12 days
Weighted average discount rate (as a percentage)	6.70%	6.70%
Accounting Standards Update 2016-02
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Other assets			$ 8,800
Operating lease liability			$ 10,800
Billerica Massachusetts | Laboratory and Office Space
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Area of real estate property (in square feet) | ft²	100	100
Billerica Massachusetts | Warehouse
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Area of real estate property (in square feet) | ft²	29	29

Leases - Future Minimum Undisco

Leases - Future Minimum Undiscounted Lease Payments (Details) $ in Thousands	Jun. 30, 2019USD ($)
Lessee, Operating Lease, Liability, Payment, Due [Abstract]
2019 (remaining)	$ 1,659
2020	2,955
2021	2,899
2022	2,575
2023	269
Thereafter	561
Total future minimum lease payments	10,918
Less: imputed interest	(1,089)
Present value of future minimum lease payments	9,829
Other current liabilities	2,333
Other long-term liabilities	$ 7,496

Leases - Summary of ROU Assets

Leases - Summary of ROU Assets and Operating Lease Liabilities (Details) $ in Thousands	Jun. 30, 2019USD ($)
Leases [Abstract]
Other assets	$ 8,020
Accrued expenses and other current liabilities	2,333
Other liabilities	7,496
Present value of future minimum lease payments	$ 9,829

Stock-Based Compensation - Sche

Stock-Based Compensation - Schedule of Stock-Based Compensation Expense Related to Share-Based Awards (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Stock-based compensation expense	$ 8,294	$ 6,937	$ 14,078	$ 15,117
Unamortized Expense	51,014		51,014
Employee stock purchase plan
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Stock-based compensation expense	318	294	718	588
Unamortized Expense	739		$ 739
Share-based compensation arrangement by share-based payment award, equity instruments other than options, outstanding, weighted average remaining contractual term			12 days
Stock options
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Stock-based compensation expense	1,583	2,272	$ 3,223	4,630
Unamortized Expense	10,906		$ 10,906
Share-based compensation arrangement by share-based payment award, options, vested and expected to vest, exercisable, weighted average remaining contractual term			2 years 8 months 12 days
Unvested restricted stock units
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Stock-based compensation expense	6,393	$ 4,371	$ 10,137	$ 9,899
Unamortized Expense	$ 39,369		$ 39,369
Share-based compensation arrangement by share-based payment award, equity instruments other than options, outstanding, weighted average remaining contractual term			2 years 2 months 12 days

Stock-Based Compensation - Stoc

Stock-Based Compensation - Stock Option Activity (Details) - USD ($) $ / shares in Units, $ in Thousands	6 Months Ended
	Jun. 30, 2019
Number of Options
Beginning balance (in shares)	3,077,624
Granted (in shares)	125,640
Exercised (in shares)	(721,041)
Canceled (in shares)	(111,604)
Ending balance (in shares)	2,370,619
Vested, at end of period (in shares)	1,839,054
Vested and expected to vest, at end of period (in shares)	2,309,525
Weighted Average Exercise Price
Beginning balance (in dollars per share)	$ 39.16
Granted (in dollars per share)	93.16
Exercised (in dollars per share)	33.42
Canceled (in dollars per share)	48.06
Ending balance (in dollars per share)	43.35
Vested, at end of period (in dollars per share)	$ 37.50
Aggregate Intrinsic Value
Exercised	$ 49,242
Ending balance	180,231
Vested, at end of period	150,573
Vested and expected to vest, at end of period	$ 177,471
Options outstanding, weighted average remaining contractual life	5 years 3 months 18 days
Options exercisable, weighted average remaining contractual life	4 years 6 months

Stock-Based Compensation - Summ

Stock-Based Compensation - Summary of Restricted Stock Units (Details) - Unvested restricted stock units	6 Months Ended
	Jun. 30, 2019$ / sharesshares
Number of Shares
Beginning balance (in shares) | shares	752,207
Granted (in shares) | shares	311,950
Vested (in shares) | shares	(307,217)
Forfeited (in shares) | shares	(51,645)
Ending balance (in shares) | shares	705,295
Weighted Average Grant Date Fair Value
Beginning balance (in dollars per share) | $ / shares	$ 55.02
Granted (in dollars per share) | $ / shares	93.79
Vested (in dollars per share) | $ / shares	45.36
Forfeited (in dollars per share) | $ / shares	63.77
Ending balance (in dollars per share) | $ / shares	$ 75.73

Interest Expense - Interest Exp

Interest Expense - Interest Expense (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018	Dec. 31, 2018
Debt Instrument [Line Items]
Contractual coupon interest	$ 2,462	$ 2,462	$ 4,924	$ 4,942
Accretion of debt discount	7,057	6,616	14,000	13,138
Amortization of debt issuance costs	692	648	1,372	1,289
Capitalized interest	(2,569)	(2,436)	(6,039)	(4,161)
Interest expense, net of portion capitalized	7,642	7,290	14,257	15,208
Non-cash interest expense	7,749	7,264	15,372	14,427
Total interest expense related to convertible debt	10,211	9,726	20,296	19,369
1.375% Convertible Senior Notes
Debt Instrument [Line Items]
Contractual coupon interest	1,384	1,383	2,768	2,767
Non-cash interest expense	3,924	3,654	7,803	7,265
Total interest expense related to convertible debt	$ 5,308	5,037	$ 10,571	10,032
Debt, interest rate	1.375%		1.375%		1.375%
1.25% Convertible Notes
Debt Instrument [Line Items]
Contractual coupon interest	$ 1,078	1,078	$ 2,156	2,156
Non-cash interest expense	3,825	3,589	7,569	7,102
Total interest expense related to convertible debt	$ 4,903	4,667	$ 9,725	9,258
Debt, interest rate	1.25%		1.25%		1.25%
2% Convertible Senior Notes
Debt Instrument [Line Items]
Contractual coupon interest	$ 0	1	$ 0	19
Non-cash interest expense	0	21	0	60
Total interest expense related to convertible debt	$ 0	$ 22	$ 0	$ 79
Debt, interest rate	2.00%		2.00%

Income Tax Expense - Narrative

Income Tax Expense - Narrative (Details)	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Income Tax Disclosure [Abstract]
Effective tax rate	25.60%	(32.20%)	12.30%	(9.90%)

Uncategorized Items - podd-2019

Label	Element	Value
Accounting Standards Update 2014-09 [Member]
Cumulative Effect of New Accounting Principle in Period of Adoption	us-gaap_CumulativeEffectOfNewAccountingPrincipleInPeriodOfAdoption	$ 20,349,000
Accounting Standards Update 2014-09 [Member] | Retained Earnings [Member]
Cumulative Effect of New Accounting Principle in Period of Adoption	us-gaap_CumulativeEffectOfNewAccountingPrincipleInPeriodOfAdoption	$ 20,349,000