Etsy (ETSY) 10-Q 7 May 20 2020 Q1 Quarterly report Financial data

Cover Page

Cover Page - shares	3 Months Ended
	Mar. 31, 2020	May 04, 2020
Cover [Abstract]
Document Type	10-Q
Document Quarterly Report	true
Document Period End Date	Mar. 31, 2020
Document Transition Report	false
Entity File Number	001-36911
Entity Registrant Name	ETSY, INC
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	20-4898921
Entity Address, Address Line One	117 Adams Street
Entity Address, City or Town	Brooklyn
Entity Address, State or Province	NY
Entity Address, Postal Zip Code	11201
City Area Code	718
Local Phone Number	880-3660
Title of 12(b) Security	Common Stock
Trading Symbol	ETSY
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)		118,677,964
Entity Central Index Key	0001370637
Current Fiscal Year End Date	--12-31
Document Fiscal Year Focus	2020
Document Fiscal Period Focus	Q1
Amendment Flag	false

Consolidated Balance Sheets (Un

Consolidated Balance Sheets (Unaudited) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Current assets:
Cash and cash equivalents	$ 442,354	$ 443,293
Short-term investments	361,640	373,959
Accounts receivable, net of expected credit losses of $6,734 and $5,033 as of March 31, 2020 and December 31, 2019, respectively	11,712	15,386
Prepaid and other current assets	36,074	38,614
Funds receivable and seller accounts	55,172	49,786
Total current assets	906,952	921,038
Restricted cash	5,341	5,341
Property and equipment, net of accumulated depreciation and amortization of $131,114 and $120,084 as of March 31, 2020 and December 31, 2019, respectively	134,519	144,864
Goodwill	138,305	138,731
Intangible assets, net of accumulated amortization of $13,377 and $16,911 as of March 31, 2020 and December 31, 2019, respectively	194,874	199,236
Deferred tax assets	15,232	14,257
Long-term investments	94,080	89,343
Other assets	28,339	29,542
Total assets	1,517,642	1,542,352
Current liabilities:
Accounts payable	10,557	26,324
Accrued expenses	68,885	88,345
Finance lease obligations—current	8,000	8,275
Funds payable and amounts due to sellers	55,172	49,786
Deferred revenue	8,250	7,617
Other current liabilities	7,985	8,181
Total current liabilities	158,849	188,528
Finance lease obligations—net of current portion	51,458	53,611
Deferred tax liabilities	63,126	64,497
Long-term debt, net	794,129	785,126
Other liabilities	43,233	43,956
Total liabilities	1,110,795	1,135,718
Commitments and contingencies (Note 10)
Stockholders’ equity:
Common stock ($0.001 par value, 1,400,000,000 shares authorized as of March 31, 2020 and December 31, 2019; 118,376,782 and 118,342,772 shares issued and outstanding as of March 31, 2020 and December 31, 2019, respectively)	118	119
Preferred stock ($0.001 par value, 25,000,000 shares authorized as of March 31, 2020 and December 31, 2019)	0	0
Additional paid-in capital	657,311	642,628
Accumulated deficit	(239,883)	(227,414)
Accumulated other comprehensive loss	(10,699)	(8,699)
Total stockholders’ equity	406,847	406,634
Total liabilities and stockholders’ equity	$ 1,517,642	$ 1,542,352

Consolidated Balance Sheets (_2

Consolidated Balance Sheets (Unaudited) (Parenthetical) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Statement of Financial Position [Abstract]
Accounts receivable, expected credit losses	$ 6,734	$ 5,033
Accumulated amortization	13,377	16,911
Property and equipment, accumulated depreciation and amortization	$ 131,114	$ 120,084
Common stock, par value (in dollars per share)	$ 0.001	$ 0.001
Common stock, shares authorized (in shares)	1,400,000,000	1,400,000,000
Common stock, shares issued (in shares)	118,376,782	118,342,772
Common stock, shares outstanding (in shares)	118,376,782	118,342,772
Preferred stock, par value (in dollars per share)	$ 0.001	$ 0.001
Preferred stock, shares authorized (in shares)	25,000,000	25,000,000

Consolidated Statements of Oper

Consolidated Statements of Operations (Unaudited) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Income Statement [Abstract]
Revenue	$ 228,055	$ 169,339
Cost of revenue	82,416	52,658
Gross profit	145,639	116,681
Operating expenses:
Marketing	48,505	35,444
Product development	37,782	24,947
General and administrative	33,987	24,647
Total operating expenses	120,274	85,038
Income from operations	25,365	31,643
Other (expense) income:
Interest expense	(9,967)	(4,653)
Interest and other income	3,613	3,385
Foreign exchange (loss) gain	(9,318)	1,062
Total other expense	(15,672)	(206)
Income before income taxes	9,693	31,437
Benefit for income taxes	2,829	142
Net income	$ 12,522	$ 31,579
Net income per share attributable to common stockholders:
Basic (in dollars per share)	$ 0.11	$ 0.26
Diluted (in dollars per share)	$ 0.10	$ 0.24
Weighted-average common shares outstanding:
Basic (in shares)	118,138,186	119,679,149
Diluted (in shares)	123,119,053	130,237,875

Consolidated Statements of Comp

Consolidated Statements of Comprehensive Income (Unaudited) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Statement of Comprehensive Income [Abstract]
Net income	$ 12,522	$ 31,579
Other comprehensive loss:
Cumulative translation adjustment	(2,671)	(1,061)
Unrealized gains on marketable securities, net of tax expense of $205 and $0, respectively	671	99
Total other comprehensive loss	(2,000)	(962)
Comprehensive income	$ 10,522	$ 30,617

Consolidated Statements of Co_2

Consolidated Statements of Comprehensive Income (Unaudited) (Parenthetical) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Statement of Comprehensive Income [Abstract]
Unrealized (losses) gains on marketable securities, tax	$ 205	$ 0

Consolidated Statements of Chan

Consolidated Statements of Changes in Stockholders’ Equity (Unaudited) - USD ($) $ in Thousands	Total	Common Stock	Additional Paid-in Capital	Accumulated Deficit	Accumulated Other Comprehensive Loss
Balance at beginning of period (in shares) at Dec. 31, 2018		119,771,702
Balance at beginning of period at Dec. 31, 2018	$ 400,898	$ 120	$ 562,033	$ (153,442)	$ (7,813)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stock-based compensation	8,616		8,616
Exercise of vested options (in shares)		534,693
Exercise of vested options	5,930	$ 1	5,929
Vesting of restricted stock units, net of shares withheld (in shares)		159,403
Vesting of restricted stock units, net of shares withheld	(5,672)		(5,672)
Stock repurchase (in shares)		(532,412)
Stock repurchase	(27,492)	$ (1)		(27,491)
Other comprehensive loss	(962)				(962)
Net income	31,579			31,579
Balance at period end at Mar. 31, 2019	$ 420,013	$ 120	570,906	(142,238)	(8,775)
Balance at period end (in shares) at Mar. 31, 2019		119,933,386
Balance at beginning of period (in shares) at Dec. 31, 2019	118,342,772	118,342,772
Balance at beginning of period at Dec. 31, 2019	$ 406,634	$ 119	642,628	(227,414)	(8,699)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stock-based compensation	$ 13,985		13,985
Exercise of vested options (in shares)	447,886	447,886
Exercise of vested options	$ 4,896		4,896
Vesting of restricted stock units, net of shares withheld (in shares)		129,230
Vesting of restricted stock units, net of shares withheld	$ (4,198)		(4,198)
Stock repurchase (in shares)	(543,106)	(543,106)
Stock repurchase	$ (24,992)	$ (1)		(24,991)
Other comprehensive loss	(2,000)				(2,000)
Net income	12,522			12,522
Balance at period end at Mar. 31, 2020	$ 406,847	$ 118	$ 657,311	$ (239,883)	$ (10,699)
Balance at period end (in shares) at Mar. 31, 2020	118,376,782	118,376,782

Condensed Consolidated Statemen

Condensed Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Cash flows from operating activities
Net income	$ 12,522	$ 31,579
Adjustments to reconcile net income to net cash provided by operating activities:
Stock-based compensation expense	13,811	8,082
Depreciation and amortization expense	15,163	10,142
Bad debt expense	3,684	1,182
Foreign exchange loss (gain)	8,157	(171)
Non-cash interest expense	8,570	3,376
Deferred income taxes	(2,829)	(142)
Other non-cash expense (income), net	530	(448)
Changes in operating assets and liabilities:
Current assets	(2,784)	(48,293)
Non-current assets	915	1,008
Current liabilities	(27,235)	25,815
Non-current liabilities	(840)	(672)
Net cash provided by operating activities	29,664	31,458
Cash flows from investing activities
Purchases of property and equipment	(567)	(683)
Development of internal-use software	(1,261)	(3,390)
Purchases of marketable securities	(101,501)	(158,883)
Sales of marketable securities	109,422	140,952
Net cash provided by (used in) investing activities	6,093	(22,004)
Cash flows from financing activities
Payment of tax obligations on vested equity awards	(4,198)	(5,672)
Repurchase of stock	(24,992)	(27,492)
Proceeds from exercise of stock options	4,896	5,930
Payment of debt issuance costs	(14)	(1,192)
Payments on finance lease obligations	(2,566)	(2,745)
Other financing, net	(5,804)	1,864
Net cash used in financing activities	(32,678)	(29,307)
Effect of exchange rate changes on cash	(4,018)	(1,458)
Net decrease in cash, cash equivalents, and restricted cash	(939)	(21,311)
Cash, cash equivalents, and restricted cash at beginning of period	448,634	372,326
Cash, cash equivalents, and restricted cash at end of period	447,695	351,015
Supplemental non-cash disclosures:
Stock-based compensation capitalized in development of capitalized software	174	534
Additions to development of internal-use software and property and equipment included in accounts payable and accrued expenses	65	1,180
Additions to intangible assets included in other current liabilities	0	1,348
Right-of-use assets obtained in exchange for new lease liabilities:
Finance leases	135	202
Reconciliation of cash, cash equivalents, and restricted cash
Total cash, cash equivalents, and restricted cash	$ 447,695	$ 351,015

Basis of Presentation and Summa

Basis of Presentation and Summary of Significant Accounting Policies	3 Months Ended
	Mar. 31, 2020
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Basis of Presentation and Summary of Significant Accounting Policies	Note 1—Basis of Presentation and Summary of Significant Accounting Policies Description of Business Etsy, Inc. (the “Company” or “Etsy”) operates two-sided online marketplaces that connect millions of passionate and creative buyers and sellers. Our primary marketplace, Etsy.com, is the global marketplace for unique and creative goods. The Company generates revenue primarily from transaction and listing fees, payments processing fees, advertising services, and shipping label sales. Basis of Consolidation The Consolidated Financial Statements include the accounts of Etsy and its wholly-owned subsidiaries. All intercompany balances and transactions have been eliminated in consolidation. Unaudited Interim Financial Information and Use of Estimates The accompanying Consolidated Balance Sheet as of March 31, 2020 , the Consolidated Statements of Operations and Comprehensive Income for the three months ended March 31, 2020 and 2019 , the Condensed Consolidated Statements of Cash Flows for the three months ended March 31, 2020 and 2019 , and the Consolidated Statements of Changes in Stockholders’ Equity for the three months ended March 31, 2020 and 2019 are unaudited. The unaudited interim financial statements have been prepared on the same basis as the annual Consolidated Financial Statements except for new accounting standards adopted as disclosed below, and, in the opinion of management, reflect all adjustments, which include only normal recurring adjustments, necessary to state fairly the Company’s financial position as of March 31, 2020 , results of operations for the three months ended March 31, 2020 and 2019 , and cash flows for the three months ended March 31, 2020 and 2019 . The future effects of the COVID-19 pandemic on the Company’s results of operations, cash flows, and financial position are unclear. The Company’s Consolidated Financial Statements presented herein reflect the latest estimates and assumptions made by management that affect the reported amounts of assets and liabilities and related disclosures as of the date of the Consolidated Financial Statements and reported amounts of revenue and expenses during the reporting periods presented. The Company believes it has used reasonable estimates and assumptions in preparing the Consolidated Financial Statements. The accounting estimates that require management’s most subjective judgments include: leases, including determining the incremental borrowing rate; income taxes, including the estimate of annual effective tax rate at interim periods and evaluation of uncertain tax positions; purchase price allocations for business combinations, valuation of the acquired intangibles purchased in a business combination, and valuation of goodwill and intangible assets; stock-based compensation; fair value of financial instruments; and provision for expected credit losses . Actual results could differ from these estimates and assumptions. The results for these interim periods are not necessarily indicative of the results to be anticipated for the full annual period or any future period due to seasonal and other factors. The financial data and the other information disclosed in the Notes to the interim financial statements related to the quarters ended March 31, 2020 and 2019 and as of March 31, 2020 are unaudited. These unaudited interim financial statements should be read in conjunction with the Company’s Annual Report on Form 10-K filed with the Securities and Exchange Commission on February 27, 2020 (the “Annual Report”). There have been no material changes in the Company’s significant accounting policies from those that were disclosed in the Annual Report other than those adopted in the quarter ended March 31, 2020 as disclosed below in Recently Adopted Accounting Pronouncements. Recently Adopted Accounting Pronouncements In December 2019, the Financial Accounting Standards Board (“FASB”) issued ASU 2019-12 —Income Taxes (Topic 740)—Simplifying the Accounting for Income Taxes , which enhances and simplifies various aspects of the income tax accounting guidance, including requirements such as tax basis step-up in goodwill obtained in a transaction that is not a business combination, ownership changes in investments, and interim-period accounting for enacted changes in tax law. The Company adopted this standard in the first quarter of 2020, effective as of January 1, 2020, on a prospective basis. The effect of this standard was not material to the Company’s Consolidated Financial Statements. In August 2018, the FASB issued ASU 2018-15 —Intangibles—Goodwill and Other—Internal-Use Software (Subtopic 350-40)—Customer’s Accounting for Implementation Costs Incurred in a Cloud Computing Arrangement That Is a Service Contract, which aligns the requirements for capitalizing implementation costs incurred in a hosting arrangement that is a service contract with the requirements for capitalizing implementation costs incurred to develop or obtain internal-use software. The new guidance is effective for annual and interim periods beginning after December 15, 2019, and early adoption is permitted. The Company adopted this standard January 1, 2020 on a prospective basis. The effect of this standard was not material to the Company’s Consolidated Financial Statements. In June 2016, the FASB issued ASU 2016-13— Financial Instruments — Credit Losses (Topic 326) — Measurement of Credit Losses on Financial Instruments , and additional changes, modifications, clarifications, or interpretations related to this guidance thereafter, which require a reporting entity to estimate credit losses on certain types of financial instruments, including accounts receivable and funds receivable and seller accounts, and present assets held at amortized cost and available-for-sale debt securities at the amount expected to be collected. The Company adopted this standard January 1, 2020 using a modified retrospective transition method. The adoption of this standard did not have a material impact on the Company's Consolidated Financial Statements on the date of its adoption. For the three months ended March 31, 2020 , our assessment of the provision for expected credit losses considered market disruptions caused by COVID-19 and estimates of expected and emerging credit and collectibility trends. The continued volatility in market conditions and evolving shifts in credit trends are difficult to predict causing variability and volatility that may have a significant impact on our provision for credit losses in future periods. Accounts Receivable : This standard requires the Company to consider forward-looking information to estimate expected credit losses in addition to its previous policy of determining the allowance by a number of factors, including age of the receivable, current economic conditions, historical losses, and management’s assessment of the financial condition of sellers on its platform. The following table provides a rollforward of the allowance for credit losses that is deducted from the amortized cost basis of accounts receivable to present the net amount expected to be collected (in thousands): As of March 31, Balance as of the beginning of period $ 5,033 Adoption of ASU 2016-13, cumulative-effect adjustment to retained earnings — Provision for expected credit losses 3,684 Amounts written off charged against the allowance (1,983 ) Balance as of the end of period $ 6,734 Available-For-Sale Debt Securities : The Company’s investment portfolio at any point in time contains investments in U.S. Government and agency securities, corporate bonds, commercial paper, certificates of deposit, cash deposits, and money market funds. The Company's investment policy is to invest in high quality, investment grade securities from diverse issuers with credit ratings higher than BBB. In accordance with its investment policy, the Company’s investments have maturities no longer than 37 months, with the average maturity of these investments maintained at 12 months or less. The Company segments its portfolio based on the underlying risk profiles of the securities and has a zero loss expectation for U.S. treasury and U.S. Government agency securities. The potential of credit losses for the remainder of the portfolio of available-for-sale debt securities is mitigated by the high quality nature of the investments. The Company regularly reviews the securities in an unrealized loss position and evaluates the current expected credit loss by considering factors such as historical experience, market data, issuer-specific factors including their credit rating, and current economic conditions. As of March 31, 2020 , the Company did not recognize any year-to-date credit loss related to available-for-sale debt securities. The Company evaluates fair values for each individual security in the investment portfolio. See “ Note 7—Marketable Securities ” for additional information on the Company’s marketable securities.

Revenue

Revenue	3 Months Ended
	Mar. 31, 2020
Revenue from Contract with Customer [Abstract]
Revenue	Note 2—Revenue The following table summarizes revenue by type of service for the periods presented (in thousands): Three Months Ended 2020 2019 Marketplace revenue $ 155,921 $ 127,168 Services revenue 72,134 42,171 Revenue $ 228,055 $ 169,339 Contract balances Deferred revenues The amount of revenue recognized in the three months ended March 31, 2020 that was included in the deferred balance at January 1, 2020 was $7.3 million .

Income Taxes

Income Taxes	3 Months Ended
	Mar. 31, 2020
Income Tax Disclosure [Abstract]
Income Taxes	Note 3—Income Taxes The Company’s provision or benefit from income taxes in interim periods is determined using an estimate of the annual effective tax rate, adjusted for discrete items, if any, that are taken into account in the relevant period. Each quarter the Company updates its estimate of the annual effective tax rate, and if its estimated tax rate changes, the Company makes a cumulative adjustment. The estimate of the annual effective income tax rate for the full year is applied to the respective interim period, taking into account year-to-date amounts and projected results for the full year. The Company’s quarterly tax provision, and its quarterly estimate of the annual effective tax rate, is subject to significant variation due to several factors, including variability in accurately predicting its income or loss before tax and the mix of jurisdictions to which they relate, taxable income or loss in each jurisdiction, changes in its stock price, audit-related developments, acquisitions, changes in its deferred tax assets and liabilities and their valuation, foreign currency gains (losses), changes in statutes, regulations, case law, and administrative practices, principles, and interpretations related to tax, including changes to the global tax framework, competition, and other laws and accounting rules in various jurisdictions, and relative changes of expenses or losses for which tax benefits are not recognized. Additionally, the effective tax rate can be more or less volatile based on the amount of income or loss before tax. For example, the impact of discrete items and non-deductible expenses on the effective tax rate is greater when income before tax is lower. For the three months ended March 31, 2020 the Company’s effective income tax rate was (29.2)% representing an income tax benefit recorded on net income before tax. The effective tax rate for the three months ended March 31, 2020 was lower than the U.S. statutory rate of 21% primarily due to excess tax benefits from employee stock-based payments, a benefit related to research and development tax credit and the impact from foreign operations that are subject to lower tax rates, partially offset by additional U.S. taxes on foreign earnings. Although management believes its tax positions and related provisions reflected in the Consolidated Financial Statements are fully supportable, it recognizes that these tax positions and related provisions may be challenged by various tax authorities. These tax positions and related provisions are reviewed on an ongoing basis and are adjusted as additional facts and information become available, including progress on tax audits, changes in interpretation of tax laws, developments in case law and closing of statute of limitations. To the extent that the ultimate results differ from the original or adjusted estimates of the Company, the effect will be recorded in the provision for income taxes. The provision for income taxes involves a significant amount of management judgment regarding interpretation of relevant facts and laws in the jurisdictions in which the Company operates. Future changes in applicable laws, projected levels of taxable income and tax planning could change the effective tax rate and tax balances recorded by the Company. In addition, tax authorities periodically review income tax returns filed by the Company and can raise issues regarding its filing positions, timing and amount of income and deductions, and the allocation of income among the jurisdictions in which the Company operates. A significant period of time may elapse between the filing of an income tax return and the ultimate resolution of an issue raised by a revenue authority with respect to that return. Any adjustments as a result of any examination, may result in additional taxes or penalties against the Company. If the ultimate result of these audits differ from original or adjusted estimates, they could have a material impact on the Company’s tax provision. The amount of unrecognized tax benefits included in the Consolidated Balance Sheets increased $0.2 million in the three months ended March 31, 2020 , from $19.9 million at December 31, 2019 to $20.1 million at March 31, 2020 . The total amount of unrecognized tax benefits that, if recognized, would favorably affect the effective tax rate is $19.6 million at March 31, 2020 . Although the timing of the resolution and/or closure of audits is highly uncertain, it is reasonably possible that the balance of gross unrecognized tax benefits could significantly change in the next 12 months. Given the number of years remaining subject to examination and the number of matters being examined, at this time, the Company is unable to estimate the full range of possible adjustments to the balance of gross unrecognized tax benefits. The Company recognizes interest and/or penalties related to uncertain tax positions in income tax expense. The amount of interest and penalties accrued in tax (benefit)/expense for the three months ended March 31, 2020 was nil , and the total amount accrued as of March 31, 2020 remained flat at $0.2 million from December 31, 2019 .

Net Income Per Share

Net Income Per Share	3 Months Ended
	Mar. 31, 2020
Earnings Per Share [Abstract]
Net Income Per Share	Note 4— Net Income Per Share The following table presents the calculation of basic and diluted net income per share for periods presented (in thousands, except share and per share amounts): Three Months Ended 2020 2019 Numerator: Net income $ 12,522 $ 31,579 Net income allocated to participating securities under the two-class method — (15 ) Net income attributable to common stockholders—basic 12,522 31,564 Dilutive effect of net income allocated to participating securities under the two-class method — 15 Net income attributable to common stockholders—diluted $ 12,522 $ 31,579 Denominator: Weighted-average common shares outstanding—basic (1) 118,138,186 119,679,149 Dilutive effect of assumed conversion of options to purchase common stock 4,000,177 4,849,246 Dilutive effect of assumed conversion of restricted stock units 980,690 1,970,865 Dilutive effect of assumed conversion of convertible debt (2) — 3,720,694 Dilutive effect of assumed conversion of restricted stock from acquisition — 17,921 Weighted-average common shares outstanding—diluted 123,119,053 130,237,875 Net income per share attributable to common stockholders—basic $ 0.11 $ 0.26 Net income per share attributable to common stockholders—diluted $ 0.10 $ 0.24 (1) 23,759 shares of unvested stock are considered participating securities and are excluded from basic shares outstanding for the three months ended March 31, 2019 . (2) Since the Company expects to settle in cash the principal outstanding under the 0.125% Convertible Senior Notes due 2026 (the “ 2019 Notes ”), it uses the treasury stock method when calculating the potential dilutive effect of the conversion spread on diluted net income per share, if applicable. The Company uses the if-converted method when calculating the dilutive effect of the 0% Convertible Senior Notes due 2023 (the “ 2018 Notes ”) for the three months ended March 31, 2020 and used the treasury stock method for the three months ended March 31, 2019 . See “ Note 9—Debt ” for more information on the 2019 Notes and the 2018 Notes . The following potential common shares were excluded from the calculation of diluted net income per share attributable to common stockholders because their effect would have been anti-dilutive for the periods presented: Three Months Ended 2020 2019 Stock options 624,906 111,444 Restricted stock units 1,144,169 174,681 Convertible senior notes 16,924,593 — Total anti-dilutive securities 18,693,668 286,125

Business Combinations

Business Combinations	3 Months Ended
	Mar. 31, 2020
Business Combinations [Abstract]
Business Combinations	Note 5—Business Combinations On August 15, 2019 , the Company acquired all of the outstanding capital stock of Reverb, a leading online marketplace dedicated to buying and selling new, used, and vintage musical instruments. The acquisition enables the Company to expand into a new vertical with a company that has a similar strategy and business model. The total cash consideration paid was $270.4 million , net of cash acquired. The acquisition was accounted for under the acquisition method of accounting. Accordingly, the purchase price was allocated to the assets acquired and liabilities assumed based upon their estimated fair values as of the date of the acquisition. The excess of the purchase price over the estimated fair value of the net assets acquired was recorded as goodwill, which consists largely of synergies and acquisition of workforce. The resulting goodwill is not expected to be deductible for tax purposes. The Company has finalized the valuation of assets acquired and liabilities assumed for the acquisition of Reverb as of December 31, 2019 . Purchase Price Allocation The following table summarizes the allocation of the purchase price (at fair value) to the assets acquired and liabilities assumed of Reverb as of August 15, 2019 (the date of acquisition) (in thousands): Final Fair Value as Adjusted Short-term investments $ 1,028 Other current assets (1) 2,902 Funds receivable and seller accounts 5,578 Property and equipment other 1,543 Developed technology 30,300 Trademark 79,400 Customer relationships 93,500 Goodwill 101,703 Other assets (1) 6,743 Other net working capital (208 ) Funds payable and amounts due to sellers (5,578 ) Other current liabilities (1) (3,684 ) Other liabilities (1) (7,333 ) Deferred tax liability, net (1) (35,485 ) Total purchase price $ 270,409 (1) Other current liabilities and other liabilities are primarily related to non-income tax related contingency reserves, which are wholly offset by an indemnification asset of $5.5 million and a deferred tax asset. Acquisition-related expenses are expensed as incurred. They were recorded in general and administrative expenses and were $0.7 million for the three months ended March 31, 2020 . They primarily related to non-recurring employee-related costs associated with the acquisition. Unaudited Supplemental Pro Forma Information The following unaudited pro forma summary presents consolidated information of the Company as if the business combination had occurred on January 1, 2018 (in thousands): Three Months Ended Revenue $ 181,159 Net income 28,017

Fair Value Measurements

Fair Value Measurements	3 Months Ended
	Mar. 31, 2020
Fair Value Disclosures [Abstract]
Fair Value Measurements	Note 6—Fair Value Measurements The Company has characterized its investments in marketable securities, based on the priority of the inputs used to value the investments, into a three-level fair value hierarchy. The fair value hierarchy gives the highest priority to quoted prices in active markets for identical assets or liabilities (Level 1), and lowest priority to unobservable inputs (Level 3). If the inputs used to measure the investments fall within different levels of the hierarchy, the categorization is based on the lowest level input that is significant to the fair value measurement of the investment. Investments recorded in the accompanying Consolidated Balance Sheets are categorized based on the inputs to valuation techniques as follows: Level 1—These are investments where values are based on unadjusted quoted prices for identical assets in an active market that the Company has the ability to access. Level 2—These are investments where values are based on quoted market prices in markets that are not active or model derived valuations in which all significant inputs are observable in active markets. Level 3—These are financial instruments where values are derived from techniques in which one or more significant inputs are unobservable. The following are the major categories of assets measured at fair value on a recurring basis as of the dates indicated (in thousands): As of March 31, 2020 Level 1 Level 2 Level 3 Total Assets Cash equivalents: Money market funds $ 300,279 $ — $ — $ 300,279 Commercial paper — 6,291 — 6,291 300,279 6,291 — 306,570 Short-term investments: Commercial paper — 26,079 — 26,079 Certificates of deposit — 23,933 — 23,933 Corporate bonds — 110,948 — 110,948 U.S. Government and agency securities 200,680 — — 200,680 200,680 160,960 — 361,640 Funds receivable and seller accounts: Money market funds 19,783 — — 19,783 19,783 — — 19,783 Long-term investments: Certificate of deposit — 2,001 — 2,001 Corporate bonds — 16,633 — 16,633 U.S. Government and agency securities 75,446 — — 75,446 75,446 18,634 — 94,080 $ 596,188 $ 185,885 $ — $ 782,073 As of December 31, 2019 Level 1 Level 2 Level 3 Total Assets Cash equivalents: Money market funds $ 228,859 $ — $ — $ 228,859 Certificate of deposit — 2,959 — 2,959 Commercial paper — 5,794 — 5,794 228,859 8,753 — 237,612 Short-term investments: Commercial paper — 29,320 — 29,320 Certificate of deposit — 26,132 — 26,132 Corporate bonds — 114,202 — 114,202 U.S. Government and agency securities 204,305 — — 204,305 204,305 169,654 — 373,959 Funds receivable and seller accounts: Money market funds 18,168 — — 18,168 18,168 — — 18,168 Long-term investments: Certificate of deposit — 4,729 — 4,729 Corporate bonds — 38,563 — 38,563 U.S. Government and agency securities 46,051 — — 46,051 46,051 43,292 — 89,343 $ 497,383 $ 221,699 $ — $ 719,082 Level 1 instruments include investments in debt securities including money market funds and U.S. Government and agency securities, which are valued based on inputs including quotes from broker-dealers or recently executed transactions in the same or similar securities. Level 2 instruments include investments in debt securities, including fixed-income funds consisting of investments in commercial paper, corporate bonds, and certificates of deposit, which are valued based on quoted market prices in markets that are not active or model derived valuations in which all significant inputs are observable in active markets. The Company did not have any Level 3 instruments as of March 31, 2020 and December 31, 2019 . The Company evaluates fair value for each individual security in the investment portfolio. See “ Note 7—Marketable Securities ” for additional information on the Company’s marketable securities measured at fair value. Disclosure of Fair Values The Company’s financial instruments that are not remeasured at fair value include the 2018 Notes and 2019 Notes (see “ Note 9—Debt ”). The Company estimates the fair value of the 2018 Notes and 2019 Notes through consideration of quoted market prices of similar instruments, classified as Level 2 as described above. The estimated fair value of the 2018 Notes was $289.6 million and $310.3 million as of March 31, 2020 and December 31, 2019 , respectively. The estimated fair value of the 2019 Notes was $442.7 million and $522.2 million as of March 31, 2020 and December 31, 2019 , respectively. The carrying value of other financial instruments, including cash, accounts receivable, accounts payable, funds receivable and seller accounts, and funds payable and amounts due to sellers approximate fair value due to the immediate or short-term maturity associated with these instruments.

Marketable Securities

Marketable Securities	3 Months Ended
	Mar. 31, 2020
Investments, Debt and Equity Securities [Abstract]
Marketable Securities	Note 7—Marketable Securities Short- and long-term investments and certain cash equivalents consist of investments in debt securities that are available-for-sale. The cost and fair value of available-for-sale securities were as follows as of the dates indicated (in thousands): Cost Gross Gross Fair Value March 31, 2020 Cash equivalents: Commercial paper $ 6,292 $ (2 ) $ 1 $ 6,291 6,292 (2 ) 1 6,291 Short-term investments: Commercial paper 26,059 (12 ) 32 26,079 Certificates of deposit 23,913 (25 ) 45 23,933 Corporate bonds 111,362 (439 ) 25 110,948 U.S. Government and agency securities 199,228 — 1,452 200,680 360,562 (476 ) 1,554 361,640 Long-term investments: Certificate of deposit 2,044 (43 ) — 2,001 Corporate bonds 17,028 (397 ) 2 16,633 U.S. Government and agency securities 74,997 (12 ) 461 75,446 94,069 (452 ) 463 94,080 $ 460,923 $ (930 ) $ 2,018 $ 462,011 December 31, 2019 Cash equivalents: Commercial paper $ 5,794 $ — $ — $ 5,794 Certificate of deposit 2,958 — 1 2,959 8,752 — 1 8,753 Short-term investments: Commercial paper 29,319 (1 ) 2 29,320 Certificates of deposit 26,129 (3 ) 6 26,132 Corporate bonds 114,068 (22 ) 156 114,202 U.S. Government and agency securities 204,246 (8 ) 67 204,305 373,762 (34 ) 231 373,959 Long-term investments: Certificate of deposit 4,727 — 2 4,729 Corporate bonds 38,582 (35 ) 16 38,563 U.S. Government and agency securities 46,017 (2 ) 36 46,051 89,326 (37 ) 54 89,343 $ 471,840 $ (71 ) $ 286 $ 472,055 All investments in an unrealized loss position are in an unrealized loss position for less than 12 months as of March 31, 2020 . See “ Note 6—Fair Value Measurements ” for additional information on the Company’s marketable securities measured at fair value.

Accrued Expenses

Accrued Expenses	3 Months Ended
	Mar. 31, 2020
Payables and Accruals [Abstract]
Accrued Expenses	Note 8—Accrued Expenses Accrued expenses consisted of the following as of the dates indicated (in thousands): As of March 31, As of December 31, Sales and use tax payable $ 29,289 $ 39,250 Vendor accruals 24,452 25,760 Payroll-related liabilities 8,935 3,774 Accrued bonus 6,209 19,561 Total accrued expenses $ 68,885 $ 88,345

Debt

Debt	3 Months Ended
	Mar. 31, 2020
Debt Disclosure [Abstract]
Debt	Note 9—Debt 2019 Convertible Debt In September 2019 , the Company issued $650.0 million aggregate principal amount of the 2019 Notes in a private placement to qualified institutional buyers pursuant to Rule 144A under the Securities Act of 1933, as amended (the “Securities Act”). The net proceeds from the sale of the 2019 Notes were $639.5 million after deducting the initial purchasers’ discount and offering expenses. The equity component of the 2019 Notes is approximately $154.0 million and is included in additional paid-in capital in the Consolidated Balance Sheets. The Company used $76.2 million of the net proceeds from the 2019 Notes offering to enter into separate capped call transactions (“2019 Capped Call Transactions”) with the initial purchasers and/or their respective affiliates. During any calendar quarter preceding June 1, 2026 in which the closing price of the Company’s common stock exceeds 130% of the applicable conversion price of the 2019 Notes on at least 20 of the last 30 consecutive trading days of the quarter, holders may in the immediate quarter following convert all or a portion of their 2019 Notes . Based on the daily closing prices of the Company’s stock during the quarter ended March 31, 2020 , holders of the 2019 Notes are not eligible to convert their 2019 Notes during the second quarter of 2020 . Based on the terms of the 2019 Notes , when a conversion notice is received, the Company has the option to pay or deliver cash, shares of the Company’s common stock, or a combination thereof. Accordingly, the Company cannot be required to settle the 2019 Notes in cash and, therefore, the 2019 Notes are classified as long-term debt as of March 31, 2020 . As of March 31, 2020 , the if-converted value of the 2019 Notes was approximately $365.1 million lower than the aggregate principal amount, or $284.9 million . The 2019 Notes are general unsecured obligations of the Company. The 2019 Notes rank senior in right of payment to all of the Company’s future indebtedness that is expressly subordinated in right of payment to the 2019 Notes ; rank equal in right of payment with all of our liabilities that are not so subordinated, including our 2018 Notes ; are effectively junior to any of the Company’s secured indebtedness; and are structurally junior to all indebtedness and liabilities (including trade payables) of the Company’s subsidiaries. The Company capitalized $10.5 million of debt issuance costs in connection with the 2019 Notes . Non-cash interest expense, including amortization of debt issuance costs, related to the 2019 Notes for the three months ended March 31, 2020 was $5.3 million . Total unamortized debt issuance costs were $7.5 million and $7.8 million as of March 31, 2020 and December 31, 2019 , respectively. The estimated fair value of the 2019 Notes was $442.7 million and $522.2 million as of March 31, 2020 and December 31, 2019 , respectively. The estimated fair value of the 2019 Notes was determined through consideration of quoted market prices for similar instruments. The fair value is classified as Level 2, as defined in “ Note 6—Fair Value Measurements .” As of March 31, 2020 , there were no other material changes related to the 2019 Notes and 2019 Capped Call Transactions compared to that disclosed in the Annual Report. 2018 Convertible Debt In March 2018 , the Company issued $345.0 million aggregate principal amount of the 2018 Notes in a private placement to qualified institutional buyers pursuant to the Securities Act. The net proceeds from the sale of the 2018 Notes were $335.0 million after deducting the initial purchasers’ discount and offering expenses. The equity component of the 2018 Notes is approximately $72.8 million and is included in additional paid-in capital in the Consolidated Balance Sheets. The Company used $34.2 million of the net proceeds from the 2018 Notes offering to enter into separate capped call transactions (“2018 Capped Call Transactions”) with the initial purchasers and/or their respective affiliates. During any calendar quarter preceding November 1, 2022 in which the closing price of the Company’s common stock exceeds 130% of the applicable conversion price of the 2018 Notes on at least 20 of the last 30 consecutive trading days of the quarter, holders may in the immediate quarter following convert all or a portion of their 2018 Notes . Based on the daily closing prices of the Company’s stock during the quarter ended March 31, 2020 , holders of the 2018 Notes are not eligible to convert their 2018 Notes during the second quarter of 2020. Based on the terms of the 2018 Notes , when a conversion notice is received, the Company has the option to pay or deliver cash, shares of the Company’s common stock, or a combination thereof. Accordingly, the Company cannot be required to settle the 2018 Notes in cash and, therefore, the 2018 Notes are classified as long-term debt as of March 31, 2020 . As of March 31, 2020 , the if-converted value of the 2018 Notes was approximately $20.6 million higher than the aggregate principal amount, or $365.6 million . The 2018 Notes are general unsecured obligations of the Company. The 2018 Notes rank senior in right of payment to all of the Company’s future indebtedness that is expressly subordinated in right of payment to the Notes; rank equal in right of payment with all of our liabilities that are not so subordinated, including our 2019 Notes ; are effectively junior to any of the Company’s secured indebtedness; and are structurally junior to all indebtedness and liabilities (including trade payables) of the Company’s subsidiaries. The Company capitalized $10.0 million of debt issuance costs in connection with the 2018 Notes . Non-cash interest expense, including amortization of debt issuance costs, related to the 2018 Notes for the three months ended March 31, 2020 and 2019 was $3.9 million and $3.7 million , respectively. Total unamortized debt issuance costs related to the 2018 Notes were $4.8 million and $5.2 million as of March 31, 2020 and December 31, 2019 , respectively. The estimated fair value of the 2018 Notes was $289.6 million and $310.3 million as of March 31, 2020 and December 31, 2019 , respectively. The estimated fair value of the 2018 Notes was determined through consideration of quoted market prices for similar instruments. The fair value is classified as Level 2, as defined in “ Note 6—Fair Value Measurements .” As of March 31, 2020 , there were no other material changes related to the 2018 Notes and 2018 Capped Call Transactions compared to that disclosed in the Annual Report. 2019 Credit Agreement On February 25, 2019 , the Company entered into a $200.0 million senior secured revolving credit facility pursuant to a Credit Agreement (the “ 2019 Credit Agreement ”) with lenders party thereto from time to time, and Citibank N.A., as administrative Agent. The 2019 Credit Agreement will mature in February 2024 . The 2019 Credit Agreement includes a letter of credit sublimit of $30.0 million and a swingline loan sublimit of $10.0 million . Borrowings under the 2019 Credit Agreement (other than swingline loans) bear interest, at the Company’s option, at (i) a base rate equal to the highest of (a) the prime rate, (b) the federal funds rate plus 0.50% , and (c) an adjusted LIBOR rate for a one-month interest period plus 1.00% , in each case plus a margin ranging from 0.25% to 0.875% or (ii) an adjusted LIBOR rate plus a margin ranging from 1.25% to 1.875% . Swingline loans under the 2019 Credit Agreement bear interest at the same base rate (plus the margin applicable to borrowings bearing interest at the base rate). These margins are determined based on the senior secured net leverage ratio (defined as secured funded debt, net of unrestricted cash up to $100 million , to EBITDA) for the preceding four fiscal quarter period. The Company is also obligated to pay other customary fees for a credit facility of this size and type, including an unused commitment fee, ranging from 0.20% to 0.35% depending on the Company’s senior secured net leverage ratio, and fees associated with letters of credit. The Company capitalized $1.4 million of debt issuance costs in connection with the 2019 Credit Agreement . Non-cash interest expense related to debt issuance costs on the 2019 Credit Agreement for the three months ended March 31, 2020 was $0.1 million . Total unamortized debt issuance costs related to the 2019 Credit Agreement were $1.1 million as of both March 31, 2020 and December 31, 2019 . At March 31, 2020 , the Company did no t have any borrowings under the 2019 Credit Agreement

Commitments and Contingencies

Commitments and Contingencies	3 Months Ended
	Mar. 31, 2020
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	Note 10—Commitments and Contingencies Legal Proceedings From time to time in the normal course of business, various other claims and litigation have been asserted or commenced against the Company. Due to uncertainties inherent in litigation and other claims, the Company can give no assurance that it will prevail in any such matters, which could subject the Company to significant liability for damages. Any claims or litigation, regardless of their success, could have an adverse effect on the Company’s results of operations, cash flows, or business and financial condition in the period the claims or litigation are resolved. Although the results of litigation and claims cannot be predicted with certainty, the Company currently believes that the final outcome of these ordinary course matters will not have a material adverse effect on its business.

Stockholders' Equity

Stockholders' Equity	3 Months Ended
	Mar. 31, 2020
Equity [Abstract]
Stockholders' Equity	Note 11—Stockholders’ Equity In November 2018, the Board of Directors approved a stock repurchase program that enables the Company to repurchase up to $200 million of its common stock. The program does not have a time limit and may be modified, suspended, or terminated at any time by the Board of Directors. The number of shares repurchased and the timing of repurchases will depend on a number of factors, including, but not limited to, stock price, trading volume, and general market conditions, along with Etsy’s working capital requirements, general business conditions, and other factors. Under the stock repurchase program, the Company may purchase shares of its common stock through various means, including open market transactions, privately negotiated transactions, tender offers, or any combination thereof. In addition, open market repurchases of common stock could be made pursuant to trading plans established pursuant to Rule 10b5-1 under the Securities Exchange Act of 1934, as amended, which would permit common stock to be repurchased at a time that the Company might otherwise be precluded from doing so under insider trading laws or self-imposed trading restrictions. The following table summarizes the Company’s cumulative share repurchase activity of the program noted above, excluding shares withheld to satisfy tax withholding obligations in connection with the vesting of employee restricted stock units (“RSUs”) (in thousands, except share and per share amounts): Shares Repurchased Average Price Paid per Share (1) Value of Shares Repurchased (1) Remaining Amount Authorized Balance as of December 31, 2019 1,924,294 $ 50.65 $ 97,500 $ 102,500 Repurchases of common stock for the three months ended: March 31, 2020 543,106 46.02 25,000 (25,000 ) Balance as of Balance as of March 31, 2020 2,467,400 $ 49.63 $ 122,500 $ 77,500 (1) Average price paid per share excludes broker commissions. Value of shares repurchased includes broker commissions.

Stock-Based Compensation

Stock-Based Compensation	3 Months Ended
	Mar. 31, 2020
Share-based Payment Arrangement [Abstract]
Stock-Based Compensation	Note 12—Stock-Based Compensation During the three months ended March 31, 2020 , the Company granted stock options and RSUs under its 2015 Equity Incentive Plan (“2015 Plan”) and, pursuant to the evergreen increase provision of the 2015 Plan, the Board of Directors approved an increase of 5,917,139 shares to the total number of shares available for issuance under the 2015 Plan effective as of January 2, 2020. At March 31, 2020 , 31,831,808 shares were authorized under the 2015 Plan and 24,638,778 shares were available for future grant. The fair value of options granted in the periods presented below using the Black-Scholes pricing model has been based on the following assumptions: Three Months Ended 2020 2019 Volatility 39.5% 39.5% Risk-free interest rate 0.6% - 1.7% 2.5% Expected term (in years) 6.15 6.15 Dividend rate —% —% The following table summarizes the activity for the Company’s options during the three months ended March 31, 2020 (in thousands, except share and per share amounts): Shares Weighted-Average Exercise Price Weighted-Average Remaining Contract Term (in years) Aggregate Intrinsic Value Outstanding at December 31, 2019 6,294,919 $ 16.26 Granted 590,601 42.56 Exercised (447,886 ) 10.93 Forfeited/Canceled (535 ) 69.89 Outstanding at March 31, 2020 6,437,099 19.04 7.40 $ 139,464 Total exercisable at March 31, 2020 3,708,091 12.38 6.86 97,817 The following table summarizes the weighted-average grant date fair value of options granted, intrinsic value of options exercised, and fair value of awards vested during the three months ended March 31, 2020 and 2019 (in thousands, except per share amounts): Three Months Ended 2020 2019 Weighted-average grant date fair value of options granted $ 16.68 $ 29.55 Intrinsic value of options exercised 20,425 28,523 Fair value of awards vested 7,385 6,083 The total unrecognized compensation expense at March 31, 2020 related to the Company’s options was $28.5 million , which will be recognized over an estimated weighted-average amortization period of 2.88 years. The following table summarizes the activity for the Company’s unvested RSUs during the three months ended March 31, 2020 : Shares Weighted-Average Unvested at December 31, 2019 2,960,413 $ 40.61 Granted 1,348,762 43.01 Vested (218,793 ) 26.55 Forfeited/Canceled (76,535 ) 40.21 Unvested at March 31, 2020 4,013,847 42.18 The total unrecognized compensation expense at March 31, 2020 related to the Company’s unvested RSUs was $150.2 million , which will be recognized over an estimated weighted-average amortization period of 3.25 years. Stock-based compensation expense included in the Consolidated Statements of Operations for the periods presented below is as follows (in thousands): Three Months Ended 2020 2019 Cost of revenue $ 1,620 $ 1,099 Marketing 1,224 631 Product development 6,801 3,520 General and administrative 4,166 2,832 Stock-based compensation expense $ 13,811 $ 8,082

Basis of Presentation and Sum_2

Basis of Presentation and Summary of Significant Accounting Policies (Policies)	3 Months Ended
	Mar. 31, 2020
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Basis of Consolidation	Basis of Consolidation The Consolidated Financial Statements include the accounts of Etsy and its wholly-owned subsidiaries. All intercompany balances and transactions have been eliminated in consolidation.
Unaudited Interim Financial Information	Unaudited Interim Financial Information and Use of Estimates The accompanying Consolidated Balance Sheet as of March 31, 2020 , the Consolidated Statements of Operations and Comprehensive Income for the three months ended March 31, 2020 and 2019 , the Condensed Consolidated Statements of Cash Flows for the three months ended March 31, 2020 and 2019 , and the Consolidated Statements of Changes in Stockholders’ Equity for the three months ended March 31, 2020 and 2019 are unaudited. The unaudited interim financial statements have been prepared on the same basis as the annual Consolidated Financial Statements except for new accounting standards adopted as disclosed below, and, in the opinion of management, reflect all adjustments, which include only normal recurring adjustments, necessary to state fairly the Company’s financial position as of March 31, 2020 , results of operations for the three months ended March 31, 2020 and 2019 , and cash flows for the three months ended March 31, 2020 and 2019 .
Use of Estimates	The Company’s Consolidated Financial Statements presented herein reflect the latest estimates and assumptions made by management that affect the reported amounts of assets and liabilities and related disclosures as of the date of the Consolidated Financial Statements and reported amounts of revenue and expenses during the reporting periods presented. The Company believes it has used reasonable estimates and assumptions in preparing the Consolidated Financial Statements. The accounting estimates that require management’s most subjective judgments include: leases, including determining the incremental borrowing rate; income taxes, including the estimate of annual effective tax rate at interim periods and evaluation of uncertain tax positions; purchase price allocations for business combinations, valuation of the acquired intangibles purchased in a business combination, and valuation of goodwill and intangible assets; stock-based compensation; fair value of financial instruments; and provision for expected credit losses . Actual results could differ from these estimates and assumptions. The results for these interim periods are not necessarily indicative of the results to be anticipated for the full annual period or any future period due to seasonal and other factors. The financial data and the other information disclosed in the Notes to the interim financial statements related to the quarters ended March 31, 2020 and 2019 and as of March 31, 2020 are unaudited. These unaudited interim financial statements should be read in conjunction with the Company’s Annual Report on Form 10-K filed with the Securities and Exchange Commission on February 27, 2020 (the “Annual Report”). There have been no material changes in the Company’s significant accounting policies from those that were disclosed in the Annual Report other than those adopted in the quarter ended March 31, 2020 as disclosed below in Recently Adopted Accounting Pronouncements.
Recently Issued and Recently Adopted Accounting Pronouncements	Recently Adopted Accounting Pronouncements In December 2019, the Financial Accounting Standards Board (“FASB”) issued ASU 2019-12 —Income Taxes (Topic 740)—Simplifying the Accounting for Income Taxes , which enhances and simplifies various aspects of the income tax accounting guidance, including requirements such as tax basis step-up in goodwill obtained in a transaction that is not a business combination, ownership changes in investments, and interim-period accounting for enacted changes in tax law. The Company adopted this standard in the first quarter of 2020, effective as of January 1, 2020, on a prospective basis. The effect of this standard was not material to the Company’s Consolidated Financial Statements. In August 2018, the FASB issued ASU 2018-15 —Intangibles—Goodwill and Other—Internal-Use Software (Subtopic 350-40)—Customer’s Accounting for Implementation Costs Incurred in a Cloud Computing Arrangement That Is a Service Contract, which aligns the requirements for capitalizing implementation costs incurred in a hosting arrangement that is a service contract with the requirements for capitalizing implementation costs incurred to develop or obtain internal-use software. The new guidance is effective for annual and interim periods beginning after December 15, 2019, and early adoption is permitted. The Company adopted this standard January 1, 2020 on a prospective basis. The effect of this standard was not material to the Company’s Consolidated Financial Statements. In June 2016, the FASB issued ASU 2016-13— Financial Instruments — Credit Losses (Topic 326) — Measurement of Credit Losses on Financial Instruments , and additional changes, modifications, clarifications, or interpretations related to this guidance thereafter, which require a reporting entity to estimate credit losses on certain types of financial instruments, including accounts receivable and funds receivable and seller accounts, and present assets held at amortized cost and available-for-sale debt securities at the amount expected to be collected. The Company adopted this standard January 1, 2020 using a modified retrospective transition method. The adoption of this standard did not have a material impact on the Company's Consolidated Financial Statements on the date of its adoption. For the three months ended March 31, 2020 , our assessment of the provision for expected credit losses considered market disruptions caused by COVID-19 and estimates of expected and emerging credit and collectibility trends. The continued volatility in market conditions and evolving shifts in credit trends are difficult to predict causing variability and volatility that may have a significant impact on our provision for credit losses in future periods. Accounts Receivable : This standard requires the Company to consider forward-looking information to estimate expected credit losses in addition to its previous policy of determining the allowance by a number of factors, including age of the receivable, current economic conditions, historical losses, and management’s assessment of the financial condition of sellers on its platform. The following table provides a rollforward of the allowance for credit losses that is deducted from the amortized cost basis of accounts receivable to present the net amount expected to be collected (in thousands): As of March 31, Balance as of the beginning of period $ 5,033 Adoption of ASU 2016-13, cumulative-effect adjustment to retained earnings — Provision for expected credit losses 3,684 Amounts written off charged against the allowance (1,983 ) Balance as of the end of period $ 6,734 Available-For-Sale Debt Securities : The Company’s investment portfolio at any point in time contains investments in U.S. Government and agency securities, corporate bonds, commercial paper, certificates of deposit, cash deposits, and money market funds. The Company's investment policy is to invest in high quality, investment grade securities from diverse issuers with credit ratings higher than BBB. In accordance with its investment policy, the Company’s investments have maturities no longer than 37 months, with the average maturity of these investments maintained at 12 months or less. The Company segments its portfolio based on the underlying risk profiles of the securities and has a zero loss expectation for U.S. treasury and U.S. Government agency securities. The potential of credit losses for the remainder of the portfolio of available-for-sale debt securities is mitigated by the high quality nature of the investments. The Company regularly reviews the securities in an unrealized loss position and evaluates the current expected credit loss by considering factors such as historical experience, market data, issuer-specific factors including their credit rating, and current economic conditions. As of March 31, 2020 , the Company did not recognize any year-to-date credit loss related to available-for-sale debt securities. The Company evaluates fair values for each individual security in the investment portfolio. See “ Note 7—Marketable Securities ” for additional information on the Company’s marketable securities.

Basis of Presentation and Sum_3

Basis of Presentation and Summary of Significant Accounting Policies (Tables)	3 Months Ended
	Mar. 31, 2020
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Accounts Receivable, Allowance for Credit Loss	The following table provides a rollforward of the allowance for credit losses that is deducted from the amortized cost basis of accounts receivable to present the net amount expected to be collected (in thousands): As of March 31, Balance as of the beginning of period $ 5,033 Adoption of ASU 2016-13, cumulative-effect adjustment to retained earnings — Provision for expected credit losses 3,684 Amounts written off charged against the allowance (1,983 ) Balance as of the end of period $ 6,734

Revenue (Tables)

Revenue (Tables)	3 Months Ended
	Mar. 31, 2020
Revenue from Contract with Customer [Abstract]
Disaggregation of Revenue	The following table summarizes revenue by type of service for the periods presented (in thousands): Three Months Ended 2020 2019 Marketplace revenue $ 155,921 $ 127,168 Services revenue 72,134 42,171 Revenue $ 228,055 $ 169,339

Net Income Per Share (Tables)

Net Income Per Share (Tables)	3 Months Ended
	Mar. 31, 2020
Earnings Per Share [Abstract]
Schedule of Calculation of Basic and Diluted Net (Loss) Income Per Share	The following table presents the calculation of basic and diluted net income per share for periods presented (in thousands, except share and per share amounts): Three Months Ended 2020 2019 Numerator: Net income $ 12,522 $ 31,579 Net income allocated to participating securities under the two-class method — (15 ) Net income attributable to common stockholders—basic 12,522 31,564 Dilutive effect of net income allocated to participating securities under the two-class method — 15 Net income attributable to common stockholders—diluted $ 12,522 $ 31,579 Denominator: Weighted-average common shares outstanding—basic (1) 118,138,186 119,679,149 Dilutive effect of assumed conversion of options to purchase common stock 4,000,177 4,849,246 Dilutive effect of assumed conversion of restricted stock units 980,690 1,970,865 Dilutive effect of assumed conversion of convertible debt (2) — 3,720,694 Dilutive effect of assumed conversion of restricted stock from acquisition — 17,921 Weighted-average common shares outstanding—diluted 123,119,053 130,237,875 Net income per share attributable to common stockholders—basic $ 0.11 $ 0.26 Net income per share attributable to common stockholders—diluted $ 0.10 $ 0.24 (1) 23,759 shares of unvested stock are considered participating securities and are excluded from basic shares outstanding for the three months ended March 31, 2019 . (2) Since the Company expects to settle in cash the principal outstanding under the 0.125% Convertible Senior Notes due 2026 (the “ 2019 Notes ”), it uses the treasury stock method when calculating the potential dilutive effect of the conversion spread on diluted net income per share, if applicable. The Company uses the if-converted method when calculating the dilutive effect of the 0% Convertible Senior Notes due 2023 (the “ 2018 Notes ”) for the three months ended March 31, 2020 and used the treasury stock method for the three months ended March 31, 2019 . See “ Note 9—Debt ” for more information on the 2019 Notes and the 2018 Notes .
Schedule of Anti-Dilutive Securities Excluded from Computation of Net (Loss) Income Per Share	The following potential common shares were excluded from the calculation of diluted net income per share attributable to common stockholders because their effect would have been anti-dilutive for the periods presented: Three Months Ended 2020 2019 Stock options 624,906 111,444 Restricted stock units 1,144,169 174,681 Convertible senior notes 16,924,593 — Total anti-dilutive securities 18,693,668 286,125

Business Combinations (Tables)

Business Combinations (Tables)	3 Months Ended
	Mar. 31, 2020
Business Combinations [Abstract]
Schedule of Purchase Price Allocation	The following table summarizes the allocation of the purchase price (at fair value) to the assets acquired and liabilities assumed of Reverb as of August 15, 2019 (the date of acquisition) (in thousands): Final Fair Value as Adjusted Short-term investments $ 1,028 Other current assets (1) 2,902 Funds receivable and seller accounts 5,578 Property and equipment other 1,543 Developed technology 30,300 Trademark 79,400 Customer relationships 93,500 Goodwill 101,703 Other assets (1) 6,743 Other net working capital (208 ) Funds payable and amounts due to sellers (5,578 ) Other current liabilities (1) (3,684 ) Other liabilities (1) (7,333 ) Deferred tax liability, net (1) (35,485 ) Total purchase price $ 270,409 (1) Other current liabilities and other liabilities are primarily related to non-income tax related contingency reserves, which are wholly offset by an indemnification asset of $5.5 million and a deferred tax asset.
Schedule of Unaudited Supplemental Pro Forma Information	The following unaudited pro forma summary presents consolidated information of the Company as if the business combination had occurred on January 1, 2018 (in thousands): Three Months Ended Revenue $ 181,159 Net income 28,017

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	3 Months Ended
	Mar. 31, 2020
Fair Value Disclosures [Abstract]
Major Categories of Assets and Liabilities Measured at Fair Value on a Recurring Basis	The following are the major categories of assets measured at fair value on a recurring basis as of the dates indicated (in thousands): As of March 31, 2020 Level 1 Level 2 Level 3 Total Assets Cash equivalents: Money market funds $ 300,279 $ — $ — $ 300,279 Commercial paper — 6,291 — 6,291 300,279 6,291 — 306,570 Short-term investments: Commercial paper — 26,079 — 26,079 Certificates of deposit — 23,933 — 23,933 Corporate bonds — 110,948 — 110,948 U.S. Government and agency securities 200,680 — — 200,680 200,680 160,960 — 361,640 Funds receivable and seller accounts: Money market funds 19,783 — — 19,783 19,783 — — 19,783 Long-term investments: Certificate of deposit — 2,001 — 2,001 Corporate bonds — 16,633 — 16,633 U.S. Government and agency securities 75,446 — — 75,446 75,446 18,634 — 94,080 $ 596,188 $ 185,885 $ — $ 782,073 As of December 31, 2019 Level 1 Level 2 Level 3 Total Assets Cash equivalents: Money market funds $ 228,859 $ — $ — $ 228,859 Certificate of deposit — 2,959 — 2,959 Commercial paper — 5,794 — 5,794 228,859 8,753 — 237,612 Short-term investments: Commercial paper — 29,320 — 29,320 Certificate of deposit — 26,132 — 26,132 Corporate bonds — 114,202 — 114,202 U.S. Government and agency securities 204,305 — — 204,305 204,305 169,654 — 373,959 Funds receivable and seller accounts: Money market funds 18,168 — — 18,168 18,168 — — 18,168 Long-term investments: Certificate of deposit — 4,729 — 4,729 Corporate bonds — 38,563 — 38,563 U.S. Government and agency securities 46,051 — — 46,051 46,051 43,292 — 89,343 $ 497,383 $ 221,699 $ — $ 719,082

Marketable Securities (Tables)

Marketable Securities (Tables)	3 Months Ended
	Mar. 31, 2020
Investments, Debt and Equity Securities [Abstract]
Cost and Fair Value of Available-for-sale Securities	The cost and fair value of available-for-sale securities were as follows as of the dates indicated (in thousands): Cost Gross Gross Fair Value March 31, 2020 Cash equivalents: Commercial paper $ 6,292 $ (2 ) $ 1 $ 6,291 6,292 (2 ) 1 6,291 Short-term investments: Commercial paper 26,059 (12 ) 32 26,079 Certificates of deposit 23,913 (25 ) 45 23,933 Corporate bonds 111,362 (439 ) 25 110,948 U.S. Government and agency securities 199,228 — 1,452 200,680 360,562 (476 ) 1,554 361,640 Long-term investments: Certificate of deposit 2,044 (43 ) — 2,001 Corporate bonds 17,028 (397 ) 2 16,633 U.S. Government and agency securities 74,997 (12 ) 461 75,446 94,069 (452 ) 463 94,080 $ 460,923 $ (930 ) $ 2,018 $ 462,011 December 31, 2019 Cash equivalents: Commercial paper $ 5,794 $ — $ — $ 5,794 Certificate of deposit 2,958 — 1 2,959 8,752 — 1 8,753 Short-term investments: Commercial paper 29,319 (1 ) 2 29,320 Certificates of deposit 26,129 (3 ) 6 26,132 Corporate bonds 114,068 (22 ) 156 114,202 U.S. Government and agency securities 204,246 (8 ) 67 204,305 373,762 (34 ) 231 373,959 Long-term investments: Certificate of deposit 4,727 — 2 4,729 Corporate bonds 38,582 (35 ) 16 38,563 U.S. Government and agency securities 46,017 (2 ) 36 46,051 89,326 (37 ) 54 89,343 $ 471,840 $ (71 ) $ 286 $ 472,055

Accrued Expenses (Tables)

Accrued Expenses (Tables)	3 Months Ended
	Mar. 31, 2020
Payables and Accruals [Abstract]
Schedule of Accrued Liabilities	Accrued expenses consisted of the following as of the dates indicated (in thousands): As of March 31, As of December 31, Sales and use tax payable $ 29,289 $ 39,250 Vendor accruals 24,452 25,760 Payroll-related liabilities 8,935 3,774 Accrued bonus 6,209 19,561 Total accrued expenses $ 68,885 $ 88,345

Stockholders' Equity (Tables)

Stockholders' Equity (Tables)	3 Months Ended
	Mar. 31, 2020
Equity [Abstract]
Class of Treasury Stock	The following table summarizes the Company’s cumulative share repurchase activity of the program noted above, excluding shares withheld to satisfy tax withholding obligations in connection with the vesting of employee restricted stock units (“RSUs”) (in thousands, except share and per share amounts): Shares Repurchased Average Price Paid per Share (1) Value of Shares Repurchased (1) Remaining Amount Authorized Balance as of December 31, 2019 1,924,294 $ 50.65 $ 97,500 $ 102,500 Repurchases of common stock for the three months ended: March 31, 2020 543,106 46.02 25,000 (25,000 ) Balance as of Balance as of March 31, 2020 2,467,400 $ 49.63 $ 122,500 $ 77,500 (1) Average price paid per share excludes broker commissions. Value of shares repurchased includes broker commissions.

Stock-Based Compensation (Table

Stock-Based Compensation (Tables)	3 Months Ended
	Mar. 31, 2020
Share-based Payment Arrangement [Abstract]
Schedule of Black-Scholes Valuation Assumptions Used to Determine Fair Value of Options Granted	The fair value of options granted in the periods presented below using the Black-Scholes pricing model has been based on the following assumptions: Three Months Ended 2020 2019 Volatility 39.5% 39.5% Risk-free interest rate 0.6% - 1.7% 2.5% Expected term (in years) 6.15 6.15 Dividend rate —% —%
Summary of Stock Option Activity	The following table summarizes the activity for the Company’s options during the three months ended March 31, 2020 (in thousands, except share and per share amounts): Shares Weighted-Average Exercise Price Weighted-Average Remaining Contract Term (in years) Aggregate Intrinsic Value Outstanding at December 31, 2019 6,294,919 $ 16.26 Granted 590,601 42.56 Exercised (447,886 ) 10.93 Forfeited/Canceled (535 ) 69.89 Outstanding at March 31, 2020 6,437,099 19.04 7.40 $ 139,464 Total exercisable at March 31, 2020 3,708,091 12.38 6.86 97,817
Summary of Intrinsic Value of Options Exercised	The following table summarizes the weighted-average grant date fair value of options granted, intrinsic value of options exercised, and fair value of awards vested during the three months ended March 31, 2020 and 2019 (in thousands, except per share amounts): Three Months Ended 2020 2019 Weighted-average grant date fair value of options granted $ 16.68 $ 29.55 Intrinsic value of options exercised 20,425 28,523 Fair value of awards vested 7,385 6,083
Summary of Weighted Average Grant Date Fair Value and Fair Value of Awards Vested	The following table summarizes the weighted-average grant date fair value of options granted, intrinsic value of options exercised, and fair value of awards vested during the three months ended March 31, 2020 and 2019 (in thousands, except per share amounts): Three Months Ended 2020 2019 Weighted-average grant date fair value of options granted $ 16.68 $ 29.55 Intrinsic value of options exercised 20,425 28,523 Fair value of awards vested 7,385 6,083
Summary of Unvested RSU Activity	The following table summarizes the activity for the Company’s unvested RSUs during the three months ended March 31, 2020 : Shares Weighted-Average Unvested at December 31, 2019 2,960,413 $ 40.61 Granted 1,348,762 43.01 Vested (218,793 ) 26.55 Forfeited/Canceled (76,535 ) 40.21 Unvested at March 31, 2020 4,013,847 42.18
Schedule of Stock-Based Compensation Expense	Stock-based compensation expense included in the Consolidated Statements of Operations for the periods presented below is as follows (in thousands): Three Months Ended 2020 2019 Cost of revenue $ 1,620 $ 1,099 Marketing 1,224 631 Product development 6,801 3,520 General and administrative 4,166 2,832 Stock-based compensation expense $ 13,811 $ 8,082

Basis of Presentation and Sum_4

Basis of Presentation and Summary of Significant Accounting Policies - Allowance for Credit Loss (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019	Jan. 01, 2020	Jan. 01, 2019
Accounts Receivable, Allowance for Credit Loss [Roll Forward]
Balance as of the beginning of period	$ 5,033
Adoption of ASU 2016-13, cumulative-effect adjustment to retained earnings			$ 0	$ 7,116
Provision for expected credit losses	3,684	$ 1,182
Amounts written off charged against the allowance	(1,983)
Balance as of the end of period	$ 6,734

Revenue - Summary of Revenue by

Revenue - Summary of Revenue by Type (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Disaggregation of Revenue [Line Items]
Revenue	$ 228,055	$ 169,339
Marketplace revenue
Disaggregation of Revenue [Line Items]
Revenue	155,921	127,168
Services revenue
Disaggregation of Revenue [Line Items]
Revenue	$ 72,134	$ 42,171

Revenue - Narrative (Details)

Revenue - Narrative (Details) $ in Millions	3 Months Ended
	Mar. 31, 2020USD ($)
Revenue from Contract with Customer [Abstract]
Revenue recognized in the period	$ 7.3

Income Taxes (Details)

Income Taxes (Details) - USD ($)	3 Months Ended
	Mar. 31, 2020	Dec. 31, 2019
Income Tax Disclosure [Abstract]
Effective income tax rate	(29.20%)
Unrecognized tax benefits, period increase	$ 200,000
Unrecognized tax benefits	20,100,000	$ 19,900,000
Unrecognized tax benefits that would impact effective tax rate favorably	19,600,000
Change in income tax penalties and interest expense	0
Income tax penalties and interest accrued	$ 200,000	$ 200,000

Net Income Per Share - Calculat

Net Income Per Share - Calculation of Basic and Diluted Net (Loss) Income Per Share (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019	Sep. 30, 2019	Mar. 31, 2018
Numerator:
Net income	$ 12,522	$ 31,579
Net income allocated to participating securities under the two-class method	0	(15)
Net income attributable to common stockholders—basic	12,522	31,564
Dilutive effect of net income allocated to participating securities under the two-class method	0	15
Net income attributable to common stockholders—diluted	$ 12,522	$ 31,579
Denominator:
Weighted average common shares outstanding—basic (in shares)	118,138,186	119,679,149
Weighted average common shares outstanding - diluted (in shares)	123,119,053	130,237,875
Net income per share attributable to common stockholders—basic (in dollars per shares)	$ 0.11	$ 0.26
Net income per share attributable to common stockholders—diluted (in dollars per share)	$ 0.10	$ 0.24
Participating securities excluded from computation of earnings per share (in shares)	18,693,668	286,125
Participating Securities
Denominator:
Participating securities excluded from computation of earnings per share (in shares)		23,759
Stock Options
Denominator:
Dilutive effect of assumed conversion (in shares)	4,000,177	4,849,246
Restricted stock units
Denominator:
Dilutive effect of assumed conversion (in shares)	980,690	1,970,865
Convertible senior notes
Denominator:
Dilutive effect of assumed conversion of convertible debt (in shares)	0	3,720,694
Restricted Stock
Denominator:
Dilutive effect of assumed conversion (in shares)	0	17,921
Convertible Senior Notes Due 2026 | Convertible Debt
Denominator:
Interest rate, stated percentage			0.125%
Convertible Senior Notes Due 2023 | Convertible Debt
Denominator:
Interest rate, stated percentage				0.00%

Net Income Per Share - Summary

Net Income Per Share - Summary of Shares Excluded from the Calculation of Diluted Net (Loss) Income Per Share (Details) - shares	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Anti-dilutive securities excluded from computation of earnings per share (in shares)	18,693,668	286,125
Stock options
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Anti-dilutive securities excluded from computation of earnings per share (in shares)	624,906	111,444
Restricted stock units
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Anti-dilutive securities excluded from computation of earnings per share (in shares)	1,144,169	174,681
Convertible senior notes
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Anti-dilutive securities excluded from computation of earnings per share (in shares)	16,924,593	0

Business Combinations - Narrati

Business Combinations - Narrative (Details) - Reverb Holdings Inc. - USD ($) $ in Millions	Aug. 15, 2019	Mar. 31, 2020
Business Acquisition [Line Items]
Cash consideration paid	$ 270.4
Acquisition-related expenses		$ 0.7

Business Combinations - Purchas

Business Combinations - Purchase Price Allocation (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019	Aug. 15, 2019
Business Acquisition [Line Items]
Goodwill	$ 138,305	$ 138,731
Reverb Holdings Inc.
Business Acquisition [Line Items]
Short-term investments			$ 1,028
Other current assets (1)			2,902
Other current assets (1)			5,578
Goodwill			101,703
Other assets (1)			6,743
Other net working capital			(208)
Funds payable and amounts due to sellers			(5,578)
Other current liabilities (1)			(3,684)
Other liabilities (1)			(7,333)
Deferred tax liability, net (1)			(35,485)
Total purchase price			270,409
Indemnification asset			5,500
Reverb Holdings Inc. | Developed technology
Business Acquisition [Line Items]
Purchase price of intangible assets			79,400
Reverb Holdings Inc. | Trademark
Business Acquisition [Line Items]
Purchase price of intangible assets			93,500
Funds receivable and seller accounts | Reverb Holdings Inc.
Business Acquisition [Line Items]
Funds receivable and seller accounts			1,543
Property and equipment other | Reverb Holdings Inc.
Business Acquisition [Line Items]
Funds receivable and seller accounts			$ 30,300

Business Combinations - Unaudit

Business Combinations - Unaudited Supplemental Pro Forma Information (Details) - Reverb Holdings Inc. $ in Thousands	3 Months Ended
	Mar. 31, 2019USD ($)
Business Acquisition [Line Items]
Revenue	$ 181,159
Net income	$ 28,017

Fair Value Measurements - Sched

Fair Value Measurements - Schedule of Major Categories of Assets and Liabilities Measured at Fair Value on a Recurring Basis (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Short-term investments	$ 361,640	$ 373,959
Long-term investments	94,080	89,343
Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash equivalents	306,570	237,612
Short-term investments	361,640	373,959
Funds receivable and seller accounts	19,783	18,168
Long-term investments	94,080	89,343
Assets	782,073	719,082
Recurring | Money market funds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash equivalents	300,279	228,859
Funds receivable and seller accounts	19,783	18,168
Recurring | Certificates of deposit
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash equivalents		2,959
Short-term investments	23,933	26,132
Long-term investments	2,001	4,729
Recurring | Commercial paper
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash equivalents	6,291	5,794
Short-term investments	26,079	29,320
Recurring | Corporate bonds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Short-term investments	110,948	114,202
Long-term investments	16,633	38,563
Recurring | U.S. Government and agency securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Short-term investments	200,680	204,305
Long-term investments	75,446	46,051
Recurring | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash equivalents	300,279	228,859
Short-term investments	200,680	204,305
Funds receivable and seller accounts	19,783	18,168
Long-term investments	75,446	46,051
Assets	596,188	497,383
Recurring | Level 1 | Money market funds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash equivalents	300,279	228,859
Funds receivable and seller accounts	19,783	18,168
Recurring | Level 1 | Certificates of deposit
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash equivalents		0
Short-term investments	0	0
Long-term investments	0	0
Recurring | Level 1 | Commercial paper
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash equivalents	0	0
Short-term investments	0	0
Recurring | Level 1 | Corporate bonds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Short-term investments	0	0
Long-term investments	0	0
Recurring | Level 1 | U.S. Government and agency securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Short-term investments	200,680	204,305
Long-term investments	75,446	46,051
Recurring | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash equivalents	6,291	8,753
Short-term investments	160,960	169,654
Funds receivable and seller accounts	0	0
Long-term investments	18,634	43,292
Assets	185,885	221,699
Recurring | Level 2 | Money market funds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash equivalents	0	0
Funds receivable and seller accounts	0	0
Recurring | Level 2 | Certificates of deposit
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash equivalents		2,959
Short-term investments	23,933	26,132
Long-term investments	2,001	4,729
Recurring | Level 2 | Commercial paper
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash equivalents	6,291	5,794
Short-term investments	26,079	29,320
Recurring | Level 2 | Corporate bonds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Short-term investments	110,948	114,202
Long-term investments	16,633	38,563
Recurring | Level 2 | U.S. Government and agency securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Short-term investments	0	0
Long-term investments	0	0
Recurring | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash equivalents	0	0
Short-term investments	0	0
Funds receivable and seller accounts	0	0
Long-term investments	0	0
Assets	0	0
Recurring | Level 3 | Money market funds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash equivalents	0	0
Funds receivable and seller accounts	0	0
Recurring | Level 3 | Certificates of deposit
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash equivalents		0
Short-term investments	0	0
Long-term investments	0	0
Recurring | Level 3 | Commercial paper
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash equivalents	0	0
Short-term investments	0	0
Recurring | Level 3 | Corporate bonds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Short-term investments	0	0
Long-term investments	0	0
Recurring | Level 3 | U.S. Government and agency securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Short-term investments	0	0
Long-term investments	$ 0	$ 0

Fair Value Measurements - Narra

Fair Value Measurements - Narrative (Details) - Convertible Debt - Reported Value Measurement - Level 2 - USD ($) $ in Millions	Mar. 31, 2020	Dec. 31, 2019
Convertible Senior Notes Due 2023
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Long-term debt, fair value	$ 289.6	$ 310.3
Convertible Senior Notes Due 2026
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Long-term debt, fair value	$ 442.7	$ 522.2

Marketable Securities - (Detail

Marketable Securities - (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Debt Securities, Available-for-sale [Line Items]
Cost	$ 460,923	$ 471,840
Gross Unrealized Holding Loss	(930)	(71)
Gross Unrealized Holding Gain	2,018	286
Fair Value	462,011	472,055
Cash Equivalents
Debt Securities, Available-for-sale [Line Items]
Cost	6,292	8,752
Gross Unrealized Holding Loss	(2)	0
Gross Unrealized Holding Gain	1	1
Fair Value	6,291	8,753
Cash Equivalents | Commercial paper
Debt Securities, Available-for-sale [Line Items]
Cost	6,292	5,794
Gross Unrealized Holding Loss	(2)	0
Gross Unrealized Holding Gain	1	0
Fair Value	6,291	5,794
Cash Equivalents | Certificates of deposit
Debt Securities, Available-for-sale [Line Items]
Cost		2,958
Gross Unrealized Holding Loss		0
Gross Unrealized Holding Gain		1
Fair Value		2,959
Short-term Investments
Debt Securities, Available-for-sale [Line Items]
Cost	360,562	373,762
Gross Unrealized Holding Loss	(476)	(34)
Gross Unrealized Holding Gain	1,554	231
Fair Value	361,640	373,959
Short-term Investments | Commercial paper
Debt Securities, Available-for-sale [Line Items]
Cost	26,059	29,319
Gross Unrealized Holding Loss	(12)	(1)
Gross Unrealized Holding Gain	32	2
Fair Value	26,079	29,320
Short-term Investments | Certificates of deposit
Debt Securities, Available-for-sale [Line Items]
Cost	23,913	26,129
Gross Unrealized Holding Loss	(25)	(3)
Gross Unrealized Holding Gain	45	6
Fair Value	23,933	26,132
Short-term Investments | Corporate bonds
Debt Securities, Available-for-sale [Line Items]
Cost	111,362	114,068
Gross Unrealized Holding Loss	(439)	(22)
Gross Unrealized Holding Gain	25	156
Fair Value	110,948	114,202
Short-term Investments | U.S. Government and agency securities
Debt Securities, Available-for-sale [Line Items]
Cost	199,228	204,246
Gross Unrealized Holding Loss	0	(8)
Gross Unrealized Holding Gain	1,452	67
Fair Value	200,680	204,305
Long-term investments
Debt Securities, Available-for-sale [Line Items]
Cost	94,069	89,326
Gross Unrealized Holding Loss	(452)	(37)
Gross Unrealized Holding Gain	463	54
Fair Value	94,080	89,343
Long-term investments | Certificates of deposit
Debt Securities, Available-for-sale [Line Items]
Cost	2,044	4,727
Gross Unrealized Holding Loss	(43)	0
Gross Unrealized Holding Gain	0	2
Fair Value	2,001	4,729
Long-term investments | Corporate bonds
Debt Securities, Available-for-sale [Line Items]
Cost	17,028	38,582
Gross Unrealized Holding Loss	(397)	(35)
Gross Unrealized Holding Gain	2	16
Fair Value	16,633	38,563
Long-term investments | U.S. Government and agency securities
Debt Securities, Available-for-sale [Line Items]
Cost	74,997	46,017
Gross Unrealized Holding Loss	(12)	(2)
Gross Unrealized Holding Gain	461	36
Fair Value	$ 75,446	$ 46,051

-Accrued Expenses (Details)

-Accrued Expenses (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Payables and Accruals [Abstract]
Sales and use tax payable	$ 29,289	$ 39,250
Vendor accruals	24,452	25,760
Payroll-related liabilities	8,935	3,774
Accrued bonus	6,209	19,561
Total accrued expenses	$ 68,885	$ 88,345

Debt - 2019 Convertible Debt (D

Debt - 2019 Convertible Debt (Details) - Convertible Debt	1 Months Ended		3 Months Ended
	Sep. 30, 2019USD ($)day	Mar. 31, 2018USD ($)	Mar. 31, 2020USD ($)	Dec. 31, 2019USD ($)
Convertible Senior Notes Due 2026
Debt Instrument [Line Items]
Debt instrument	$ 650,000,000
Proceeds from issuance of convertible senior notes	639,500,000
Equity component	$ 154,000,000
Threshold percentage of stock price trigger	130.00%
Threshold trading days | day	20
Threshold consecutive trading days | day	30
If-converted value lower than principal			$ 365,100,000
If-converted value			284,900,000
Capitalization of debt issuance costs	$ 10,500,000
Non-cash interest expense			5,300,000
Unamortized debt issuance expense			7,500,000	$ 7,800,000
Capped Call Transaction
Debt Instrument [Line Items]
Proceeds from issuance of convertible senior notes	$ 76,200,000	$ 34,200,000
Reported Value Measurement | Level 2 | Convertible Senior Notes Due 2026
Debt Instrument [Line Items]
Long-term debt, fair value			$ 442,700,000	$ 522,200,000

Debt - 2018 Convertible Debt (D

Debt - 2018 Convertible Debt (Details) - Convertible Debt	Mar. 31, 2020USD ($)	Sep. 30, 2019USD ($)	Mar. 31, 2018USD ($)day	Mar. 31, 2020USD ($)	Mar. 31, 2019USD ($)	Dec. 31, 2019USD ($)
Convertible Senior Notes Due 2023
Debt Instrument [Line Items]
Debt instrument			$ 345,000,000
Proceeds from issuance of convertible senior notes			335,000,000
Equity component			$ 72,800,000
Threshold percentage of stock price trigger			130.00%
Threshold trading days | day			20
Threshold consecutive trading days | day			30
If-converted value in excess of principal	$ 20,600,000
If-converted value	365,600,000			$ 365,600,000
Capitalization of debt issuance costs			$ 10,000,000
Non-cash interest expense				3,900,000	$ 3,700,000
Unamortized debt issuance expense	4,800,000			4,800,000		$ 5,200,000
Capped Call Transaction
Debt Instrument [Line Items]
Proceeds from issuance of convertible senior notes		$ 76,200,000	$ 34,200,000
Level 2 | Reported Value Measurement | Convertible Senior Notes Due 2023
Debt Instrument [Line Items]
Long-term debt, fair value	$ 289,600,000			$ 289,600,000		$ 310,300,000

Debt - 2019 Credit Agreement (D

Debt - 2019 Credit Agreement (Details) - Credit Agreement - USD ($)	Feb. 25, 2019	Mar. 31, 2020
Line of Credit Facility [Line Items]
Capitalization of debt issuance costs	$ 1,400,000
Non-cash interest expense		$ 100,000
Unamortized debt issuance expense		1,100,000
Revolving Credit Facility
Line of Credit Facility [Line Items]
Line of credit, maximum borrowing capacity	200,000,000
Maximum unrestricted cash	100,000,000
Line of credit facility, amount outstanding		$ 0
Letter of Credit
Line of Credit Facility [Line Items]
Line of credit, maximum borrowing capacity	30,000,000
Bridge Loan
Line of Credit Facility [Line Items]
Line of credit, maximum borrowing capacity	$ 10,000,000
Federal Funds Effective Swap Rate | Revolving Credit Facility
Line of Credit Facility [Line Items]
Basis spread on variable rate	0.50%
London Interbank Offered Rate (LIBOR) | Revolving Credit Facility
Line of Credit Facility [Line Items]
Basis spread on variable rate	1.00%
Minimum | Revolving Credit Facility
Line of Credit Facility [Line Items]
Commitment fee amount	0.20%
Minimum | One-Month London Interbank Offered Rate (LIBOR) Plus 1% | Revolving Credit Facility
Line of Credit Facility [Line Items]
Basis spread on variable rate	0.25%
Minimum | London Interbank Offered Rate (LIBOR), Adjusted | Revolving Credit Facility
Line of Credit Facility [Line Items]
Basis spread on variable rate	1.25%
Maximum | Revolving Credit Facility
Line of Credit Facility [Line Items]
Commitment fee amount	0.35%
Maximum | One-Month London Interbank Offered Rate (LIBOR) Plus 1% | Revolving Credit Facility
Line of Credit Facility [Line Items]
Basis spread on variable rate	0.875%
Maximum | London Interbank Offered Rate (LIBOR), Adjusted | Revolving Credit Facility
Line of Credit Facility [Line Items]
Basis spread on variable rate	1.875%

Stockholders' Equity - (Details

Stockholders' Equity - (Details) - USD ($)	Mar. 31, 2020	Dec. 31, 2019	Mar. 31, 2020	Nov. 30, 2018
Equity [Abstract]
Stock repurchase program, authorized amount				$ 200,000,000
Shares Repurchased (in shares)	2,467,400	1,924,294	543,106
Average Price Paid per Share (in dollars per share)	$ 49.63	$ 50.65	$ 46.02
Stock repurchased and retired during period, value, including broker fees	$ (122,500,000)	$ (97,500,000)	$ (25,000,000)
Remaining Amount Authorized	$ 77,500,000	$ 102,500,000	$ 77,500,000

Stock-Based Compensation - Addi

Stock-Based Compensation - Additional Information (Details) $ in Millions	3 Months Ended
	Mar. 31, 2020USD ($)shares
Stock options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total unrecognized compensation | $	$ 28.5
Total unrecognized compensation, period of recognition	2 years 10 months 17 days
RSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total unrecognized compensation, period of recognition	3 years 3 months
Total unrecognized compensation | $	$ 150.2
2015 Equity Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Maximum number of additional shares issued annually (in shares)	5,917,139
Number of shares authorized (in shares)	31,831,808
Number of shares available for grant (in shares)	24,638,778

Stock-Based Compensation - Fair

Stock-Based Compensation - Fair Value of Options Granted Using the Black-Scholes Pricing Model (Details) - Stock options	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Volatility	39.50%	39.50%
Risk-free interest rate - minimum	0.60%
Risk-free interest rate - maximum	1.70%
Risk-free interest rate		2.50%
Expected term	6 years 1 month 24 days	6 years 1 month 24 days
Dividend rate	0.00%	0.00%

Stock-Based Compensation - Summ

Stock-Based Compensation - Summary of Stock Option Activity (Details) $ / shares in Units, $ in Thousands	3 Months Ended
	Mar. 31, 2020USD ($)$ / sharesshares
Shares
Outstanding, beginning balance (in shares) | shares	6,294,919
Granted (in shares) | shares	590,601
Exercised (in shares) | shares	(447,886)
Forfeited/Canceled (in shares) | shares	(535)
Outstanding, ending balance (in shares) | shares	6,437,099
Total exercisable (in shares) | shares	3,708,091
Weighted-Average Exercise Price
Outstanding, beginning balance (in dollars per share) | $ / shares	$ 16.26
Granted (in dollars per share) | $ / shares	42.56
Exercised (in dollars per share) | $ / shares	10.93
Forfeited/Canceled (in dollars per share) | $ / shares	69.89
Outstanding, ending balance (in dollars per share) | $ / shares	19.04
Total exercisable (in dollars per share) | $ / shares	$ 12.38
Weighted-Average Remaining Contract Term (in years)
Outstanding, Weighted-Average Remaining Contract Term	7 years 4 months 24 days
Total exercisable, Weighted-Average Remaining Contract Term	6 years 10 months 9 days
Aggregate Intrinsic Value
Outstanding, Aggregate Intrinsic Value | $	$ 139,464
Total exercisable, Aggregate Intrinsic Value | $	$ 97,817

Stock-Based Compensation - Weig

Stock-Based Compensation - Weighted Average Grant Date Fair Value of Options Granted, Intrinsic Value of Options Exercised and Fair Value of Awards Vested (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Share-based Payment Arrangement [Abstract]
Weighted average grant date fair value of options (in dollars per share)	$ 16.68	$ 29.55
Intrinsic value of options exercised	$ 20,425	$ 28,523
Fair value of awards vested	$ 7,385	$ 6,083

Stock-Based Compensation - Su_2

Stock-Based Compensation - Summary of Unvested RSUs (Details) - RSUs	3 Months Ended
	Mar. 31, 2020$ / sharesshares
Shares
Unvested at December 31, 2018 (in shares) | shares	2,960,413
Granted (in shares) | shares	1,348,762
Vested (in shares) | shares	(218,793)
Forfeited/Cancelled (in shares) | shares	(76,535)
Unvested at September 30, 2019 (in shares) | shares	4,013,847
Weighted-Average Grant Date Fair Value
Unvested at December 31, 2018 (in dollars per share) | $ / shares	$ 40.61
Granted (in dollars per share) | $ / shares	43.01
Vested (in dollars per share) | $ / shares	26.55
Forfeited/Cancelled (in dollars per share) | $ / shares	40.21
Unvested at September 30, 2019 (in dollars per share) | $ / shares	$ 42.18

Stock-Based Compensation - Allo

Stock-Based Compensation - Allocated Share-Based Compensation Expense (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation expense	$ 13,811	$ 8,082
Cost of revenue
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation expense	1,620	1,099
Marketing
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation expense	1,224	631
Product development
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation expense	6,801	3,520
General and administrative
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation expense	$ 4,166	$ 2,832

Uncategorized Items - etsy33120

Label	Element	Value
Retained Earnings [Member]
Cumulative Effect of New Accounting Principle in Period of Adoption	us-gaap_CumulativeEffectOfNewAccountingPrincipleInPeriodOfAdoption	$ 7,116,000