Etsy (ETSY) 10-Q 9 May 18 2018 Q1 Quarterly report Financial data

Document and Entity Information

Document and Entity Information - shares	3 Months Ended
	Mar. 31, 2018	May 04, 2018
Document and Entity Information [Abstract]
Entity Registrant Name	ETSY INC
Entity Central Index Key	1,370,637
Current Fiscal Year End Date	--12-31
Entity Filer Category	Large Accelerated Filer
Document Type	10-Q
Document Period End Date	Mar. 31, 2018
Document Fiscal Year Focus	2,018
Document Fiscal Period Focus	Q1
Amendment Flag	false
Entity Common Stock, Shares Outstanding		119,475,520

Consolidated Balance Sheets (Un

Consolidated Balance Sheets (Unaudited) - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
Current assets:
Cash and cash equivalents	$ 533,855	$ 315,442
Short-term investments	67,526	25,108
Accounts receivable, net of allowance for doubtful accounts of $3,075 and $2,687 as of March 31, 2018 and December 31, 2017, respectively	31,292	33,677
Prepaid and other current assets	23,738	20,379
Funds receivable and seller accounts	48,586	44,658
Total current assets	704,997	439,264
Restricted cash	5,341	5,341
Property and equipment, net of accumulated depreciation and amortization of $71,291 and $66,226 as of March 31, 2018 and December 31, 2017, respectively	116,385	117,617
Goodwill	39,228	38,541
Intangible assets, net of accumulated amortization of $3,700 and $3,100 as of March 31, 2018 and December 31, 2017, respectively	3,500	4,100
Other assets	714	720
Total assets	870,165	605,583
Current liabilities:
Accounts payable	8,094	13,622
Accrued expenses	35,384	28,743
Capital lease obligations—current	4,861	5,798
Funds payable and amounts due to sellers	48,586	44,658
Deferred revenue	6,464	6,262
Other current liabilities	3,167	3,394
Total current liabilities	106,556	102,477
Capital lease obligations—net of current portion	3,231	4,115
Deferred tax liabilities	32,303	23,786
Facility financing obligation	60,041	60,049
Long-term debt, net	265,415	0
Other liabilities	18,132	18,262
Total liabilities	485,678	208,689
Commitments and Contingencies
Stockholders’ equity:
Common stock ($0.001 par value, 1,400,000,000 shares authorized as of March 31, 2018 and December 31, 2017; 119,954,600 and 121,769,238 shares issued and outstanding as of March 31, 2018 and December 31, 2017, respectively)	120	122
Preferred Stock ($0.001 par value, 25,000,000 shares authorized as of March 31, 2018 and December 31, 2017)	0	0
Additional paid-in capital	542,554	499,441
Accumulated deficit	(151,906)	(96,290)
Accumulated other comprehensive loss	(6,281)	(6,379)
Total stockholders’ equity	384,487	396,894
Total liabilities and stockholders’ equity	$ 870,165	$ 605,583

Consolidated Balance Sheets (U3

Consolidated Balance Sheets (Unaudited) (Parenthetical) - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
Statement of Financial Position [Abstract]
Net of allowance for doubtful accounts	$ 3,075	$ 2,687
Accumulated depreciation and amortization	71,291	66,226
Accumulated amortization, intangible assets	$ 3,700	$ 3,100
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)	119,954,600	121,769,238
Common stock, shares outstanding (in shares)	119,954,600	121,769,238
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, 2018	Mar. 31, 2017
Income Statement [Abstract]
Revenue	$ 120,912	$ 96,891
Cost of revenue	41,295	34,659
Gross profit	79,617	62,232
Operating expenses:
Marketing	26,194	23,454
Product development	20,721	18,116
General and administrative	18,904	22,763
Total operating expenses	65,819	64,333
Income (loss) from operations	13,798	(2,101)
Other (expense) income:
Interest expense	(3,764)	(2,591)
Interest and other income	1,097	439
Foreign exchange gain	1,850	2,780
Total other (expense) income	(817)	628
Income (loss) before income taxes	12,981	(1,473)
(Provision) benefit for income taxes	(14)	1,052
Net income (loss)	$ 12,967	$ (421)
Net income (loss) per share attributable to common stockholders:
Basic (in dollars per share)	$ 0.11	$ 0
Diluted (in dollars per share)	$ 0.10	$ 0
Weighted-average common shares outstanding:
Basic (in shares)	121,267,092	115,696,024
Diluted (in shares)	125,772,315	115,696,024

Consolidated Statements of Comp

Consolidated Statements of Comprehensive Income (Loss) (Unaudited) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Statement of Comprehensive Income [Abstract]
Net income (loss)	$ 12,967	$ (421)
Other comprehensive income (loss):
Cumulative translation adjustment	124	(2,955)
Unrealized losses on marketable securities, net of tax	(26)	(22)
Total other comprehensive income (loss)	98	(2,977)
Comprehensive income (loss)	$ 13,065	$ (3,398)

Consolidated Statement of Chang

Consolidated Statement of Changes in Stockholders’ Equity (Unaudited) - 3 months ended Mar. 31, 2018 - USD ($) $ in Thousands	Total	Common Stock	Additional Paid-in Capital	Accumulated Deficit	Accumulated Other Comprehensive Loss
Balance at beginning of period at Dec. 31, 2017	$ 396,894	$ 122	$ 499,441	$ (96,290)	$ (6,379)
Balance at beginning of period (in shares) at Dec. 31, 2017		121,769,238
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Adjustments to Additional Paid in Capital, Share-based Compensation, Requisite Service Period Recognition	5,990		5,990
Exercise of vested options	$ 10,249	$ 1	10,248
Exercise of vested options (in shares)	887,906	887,906
Issuance of convertible senior notes, net of issuance costs and taxes	$ 54,184		54,184
Purchase of capped call, net of taxes	(26,243)		(26,243)
Vesting of restricted stock units, net of shares withheld	(1,780)		(1,780)
Vesting of restricted stock units, net of shares withheld (in shares)		104,849
Stock repurchase	$ (68,586)	$ (3)	0	(68,583)
Stock repurchase (in shares)	(2,807,393)	(2,807,393)
Stock-based compensation—acquisitions	$ 714		714
Other comprehensive income	98				98
Net income	12,967			12,967
Balance at period end at Mar. 31, 2018	$ 384,487	$ 120	$ 542,554	$ (151,906)	$ (6,281)
Balance at period end (in shares) at Mar. 31, 2018		119,954,600

Consolidated Statements of Cash

Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Cash flows from operating activities
Net income (loss)	$ 12,967	$ (421)
Adjustments to reconcile net income (loss) to net cash provided by operating activities:
Stock-based compensation expense	5,740	4,043
Stock-based compensation expense—acquisitions	714	842
Depreciation and amortization expense	6,320	6,938
Bad debt expense	912	332
Foreign exchange gain	(1,850)	(2,780)
Amortization of debt issuance costs	122	56
Non-cash interest expense	1,077	2,145
Interest on marketable securities	(80)	277
(Gain) loss on disposal of assets	(4)	49
Deferred income taxes	91	0
Changes in operating assets and liabilities:
Accounts receivable	1,684	1,093
Funds receivable and seller accounts	(3,540)	(4,351)
Prepaid expenses and other current assets	(2,461)	(4,385)
Other assets	7	(28)
Accounts payable	(6,620)	(3,404)
Accrued and other current liabilities	5,550	(2,234)
Funds payable and amounts due to sellers	3,540	4,351
Deferred revenue	157	109
Other liabilities	2,095	677
Net cash provided by operating activities	26,421	3,309
Cash flows from investing activities
Purchases of property and equipment	(192)	(2,700)
Development of internal-use software	(3,097)	(3,956)
Purchases of marketable securities	(59,811)	(23,240)
Sales of marketable securities	17,447	42,290
Net cash (used in) provided by investing activities	(45,653)	12,394
Cash flows from financing activities
Repurchase of stock for tax on RSU vesting	(1,780)	(797)
Repurchase of stock	(68,586)	0
Proceeds from exercise of stock options	10,249	600
Proceeds from issuance of convertible senior notes	345,000	0
Payment of debt issuance costs	(9,127)	0
Purchase of capped call	(34,224)	0
Payments on capital lease obligations	(1,850)	(1,835)
Payments on facility financing obligation	(3,122)	0
Net cash provided by (used in) financing activities	236,560	(2,032)
Effect of exchange rate changes on cash	1,085	(456)
Net increase in cash, cash equivalents and restricted cash	218,413	13,215
Cash, cash equivalents and restricted cash at beginning of period	320,783	186,933
Cash, cash equivalents and restricted cash at end of period	539,196	200,148
Supplemental non-cash disclosures
Equipment acquired under capital lease obligations	29	1,068
Stock-based compensation capitalized in development of capitalized software	250	306
Additions to development of internal-use software and property and equipment included in accounts payable and accrued expenses	1,535	358
Debt issuance costs included in accrued expenses	$ 977	$ 0

Basis of Presentation and Summa

Basis of Presentation and Summary of Significant Accounting Policies	3 Months Ended
	Mar. 31, 2018
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”) is the global marketplace for unique and creative goods. The Company generates revenue primarily from transaction and listing fees, Etsy Payments fees, Promoted Listing fees, Shipping Label sales, and Pattern by Etsy fees. 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. Reclassifications Certain items in the prior years’ Consolidated Financial Statements have been reclassified to conform to the current year presentation reflected in the Consolidated Financial Statements. Specifically, the Company reclassified $29.8 million previously included in Services revenue to Marketplace revenue (see “ Note 2—Revenue ”) for the the three months ended March 31, 2017 to conform to the current year presentation in connection with the adoption of Accounting Standards Codification (“ASC”) 606, Revenue from Contracts with Customers . Additionally, the Company reclassified $5.3 million on the Consolidated Statement of Cash Flows in the three months ended March 31, 2017 to include restricted cash in the beginning and ending cash, cash equivalent and restricted cash balances to conform to the current year presentation upon adoption of Accounting Standards Update (“ASU”) 2016-18, Statement of Cash Flows: Restricted Cash. Unaudited Interim Financial Information The accompanying Consolidated Balance Sheet as of March 31, 2018 , the Consolidated Statements of Operations and Comprehensive Income (Loss) for the three months ended March 31, 2018 and 2017 , the Consolidated Statements of Cash Flows for the three months ended March 31, 2018 and 2017 and the Consolidated Statement of Changes in Stockholders’ Equity for the three months ended March 31, 2018 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 of January 1, 2018 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, 2018 , results of operations for the three months ended March 31, 2018 and 2017 and cash flows for the three months ended March 31, 2018 and 2017 . The results from these interim periods are not necessarily indicative of the results to be anticipated for the full annual period or any future period. The financial data and the other information disclosed in these Notes to the Consolidated Financial Statements related to these three month periods 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 March 1, 2018 (the “Annual Report”). During the first quarter of 2018, the Company adopted the accounting principles outlined within ASU 2014-09, Revenue from Contracts with Customers , and ASU 2016-18, Statement of Cash Flows: Restricted Cash, described below . There have been no additional material changes in the Company's significant accounting policies from those that were disclosed in the Annual Report. Use of Estimates The preparation of the Company’s Consolidated Financial Statements in conformity with accounting principles generally accepted in the United States of America (“GAAP”) requires management to make estimates and judgments that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of revenues and expenses during the reporting period. The accounting estimates that require management’s most difficult and subjective judgments include: for revenue recognition, determining the nature and timing of satisfaction of performance obligations; income taxes; website development costs and internal-use software; purchase price allocations for business combinations; valuation of goodwill and intangible assets; leases; stock-based compensation; restructuring and other exit costs (income); and fair value of financial instruments. The Company evaluates its estimates and judgments on an ongoing basis and revises them when necessary. Actual results may differ from the original or revised estimates. Revenue Recognition The Company’s revenue is diversified; generated from a mix of marketplace activities and other optional services to help Etsy sellers start, manage and scale their business. Revenues are recognized as the Company transfers control of promised goods or services to Etsy sellers, in an amount that reflects the consideration the Company expects to be entitled to in exchange for those goods or services. The Company evaluates whether it is appropriate to recognize revenue on a gross or net basis based upon its evaluation of whether the Company obtains control of the specified goods or services by considering if it is primarily responsible for fulfillment of the promise, has inventory risk and has the latitude in establishing pricing and selecting suppliers, among other factors. Based on its evaluation of these factors, revenue is recorded either gross or net of costs associated with the transaction. Sales and usage-based taxes are excluded from revenues. See “ Note 2—Revenue ” for additional information regarding revenue recognition. Income Taxes The Company's income tax (provision) benefit for interim periods is determined using an estimate of its annual effective tax rate adjusted for discrete items, if any, for relevant interim periods. The Company updates its estimate of the annual effective tax rate each quarter and makes cumulative adjustments if its estimated annual tax rate changes. The Company's quarterly tax provision and quarterly estimate of its annual effective tax rate are subject to significant variations due to several factors, including variability in predicting its pretax and taxable income and the mix of jurisdictions to which those relate, changes of expenses or losses for which tax benefits are not recognized, recording of excess tax benefits related to stock-based compensation and changes in the laws, regulations and administrative practices of the jurisdictions in which the Company operates. Net Income (Loss) Per Share Basic net income (loss) per share attributable to common stockholders is computed by dividing the net income (loss) attributable to common stockholders by the weighted-average number of common shares outstanding for the period. Diluted net income (loss) per share is computed by dividing net income (loss) for the period by the weighted-average number of shares of common stock and potentially dilutive common stock outstanding during the period. The dilutive effect of outstanding options and stock-based compensation awards is reflected in diluted net income (loss) per share by application of the treasury stock method. Since the Company expects to settle in cash the principal outstanding under the 0% Convertible Senior Notes due 2023 the Company issued in March 2018 (the “Notes,” see “ Note 3—Convertible Debt ”) it uses the treasury stock method when calculating their potential dilutive effect of the conversion spread on diluted net income per share, if applicable. The conversion spread will have a dilutive impact on diluted net income per share of common stock when the average market price of the Company's common stock for a given period exceeds the conversion price of $36.27 per share. The calculation of diluted net income (loss) per share excludes all anti-dilutive common shares. For periods in which the Company has reported net losses, diluted net loss per share attributable to common stockholders is the same as basic net loss per share attributable to common stockholders, because dilutive common shares are not assumed to have been issued if their effect is anti-dilutive. Recently Issued Accounting Pronouncements In February 2016, the Financial Accounting Standards Board (“FASB”) issued ASU 2016-02, Leases , and additional changes, modifications, clarifications or interpretations related to this guidance thereafter, which require a reporting entity to recognize right-of-use assets and lease liabilities on the balance sheet for operating leases to increase transparency and comparability. The new guidance is effective for annual and interim periods beginning after December 15, 2018, and early adoption is permitted. Upon adoption of this standard, the Company expects to recognize, on a discounted basis, its minimum commitments under noncancelable operating leases on the Consolidated Balance Sheets resulting in the recording of right-of-use assets and lease obligations. The Company is currently evaluating whether there are any additional impacts this guidance will have on its Consolidated Financial Statements. Recently Adopted Accounting Pronouncements In May 2014, the FASB issued ASU 2014-09, Revenue from Contracts with Customers , and additional changes, modifications, clarifications or interpretations related to this guidance thereafter, which replaces existing revenue recognition guidance. The new guidance is effective for the annual and interim periods beginning after December 15, 2017. Among other things, the updated guidance requires companies to recognize revenue in a way that depicts the transfer of promised goods or services to customers in an amount that reflects the consideration to which the entity expects to be entitled in exchange for those goods or services. The Company adopted the requirements of the new guidance as of January 1, 2018, utilizing the full retrospective method of transition. Adoption of the new guidance did not result in changes to the prior year or current year Consolidated Financial Statements. See “ Note 2—Revenue ” for additional information regarding revenue recognition. In November 2016, the FASB issued ASU 2016-18, Statement of Cash Flows: Restricted Cash , which requires that a statement of cash flows explain the change during the period in the total of cash, cash equivalents and amounts generally described as restricted cash or restricted cash equivalents. The new guidance is effective for the annual and interim periods beginning after December 15, 2017. The Company adopted this standard in the first quarter of 2018 utilizing the full retrospective method of transition. As a result of this guidance, the Company reclassified $5.3 million on the Consolidated Statement of Cash Flows in the three months ended March 31, 2018 and 2017 to include restricted cash in the beginning and ending cash, cash equivalent and restricted cash balances. The following table provides a reconciliation of cash, cash equivalents and restricted cash reported within the Consolidated Balance Sheets that sum to the total of the same such amounts shown in the Consolidated Statement of Cash Flows (in thousands): Three Months Ended March 31, 2018 2017 Beginning balance: Cash and cash equivalents $ 315,442 $ 181,592 Restricted cash 5,341 5,341 Total cash, cash equivalents and restricted cash $ 320,783 $ 186,933 Ending balance: Cash and cash equivalents $ 533,855 $ 194,807 Restricted cash 5,341 5,341 Total cash, cash equivalents and restricted cash $ 539,196 $ 200,148 The balances included in restricted cash represent amounts held as collateral associated with the lease of the Company's Brooklyn, New York headquarters. This standard had no other impact to the Consolidated Financial Statements.

Revenue

Revenue	3 Months Ended
	Mar. 31, 2018
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 2018 2017 Marketplace revenue (1) $ 87,967 $ 70,562 Services revenue 32,605 24,144 Other revenue 340 2,185 Revenue $ 120,912 $ 96,891 (1) Etsy Payments revenue for the three months ended March 31, 2018 has been classified and presented within Marketplace revenue. Comparative periods have been reclassified to conform to current period presentation. Marketplace Revenue : As members of the Etsy marketplace, Etsy sellers receive the benefit of marketplace activities, including listing items for sale, completing sales transactions, and payments processing, which represents a single stand-ready performance obligation. Etsy sellers pay a fixed listing fee of $0.20 for each item listed on Etsy.com for the earlier of a period of four months or until a sale occurs. Variable fees include the 3.5% transaction fee that an Etsy seller pays for each completed transaction, exclusive of shipping fees charged, and Etsy Payments fees for processing payments, including foreign currency payments. Etsy Payments processing fees vary between 3 - 4% of an item’s total sale price, including shipping, plus a flat fee per order, depending on the country in which a seller's bank account is located. When a foreign currency payment is processed, an additional 2.5 - 5% transaction fee is applied. The listing fee is recognized ratably over a four -month listing period, unless the item is sold or the seller relists it, at which time any remaining listing fee is recognized. The 3.5% transaction fee and Etsy Payments fees are recognized when the corresponding transaction is consummated. Listing fees are nonrefundable while transaction fees and Etsy Payments fees are recorded net of refunds. Services revenue : Services revenue is derived from optional services offered to Etsy sellers, which include Promoted Listings, Etsy Shipping Labels, and Pattern by Etsy. Each service below represents an individual obligation that the Company must perform when an Etsy seller chooses to use the service. • Revenue from Promoted Listings, the Company's on-site advertising service, consists of cost-per-click fees an Etsy seller pays for prominent placement of the seller's listings in search results in the Company's marketplace. Promoted Listings fees are based on an auction system, which utilizes the budget that each Etsy seller sets when using Promoted Listings to determine the cost-per-click fee. Promoted Listing fees are nonrefundable and are charged to a seller’s Etsy bill when the Promoted Listing is clicked; at which time revenue is recognized. • Revenue from Etsy Shipping Labels consists of fees an Etsy seller pays the Company when the seller purchases shipping labels through our platform, net of the cost the Company incurs in purchasing those shipping labels. The Company provides sellers access to purchase shipping labels from the United States Postal Service, FedEx, and Canada Post at discounted pricing due to the volume of purchases through its platform. The Company recognizes Etsy Shipping Label revenue when an Etsy seller purchases a shipping label. The Company recognizes Shipping Label revenue on a net basis as the Company is an agent in this arrangement and does not take ownership of shipping labels prior to transferring the labels to the Etsy Seller. Etsy Shipping Labels revenue is recorded net of refunds. • Revenue from Pattern by Etsy consists of monthly subscription fees an Etsy seller pays to use the Company's custom website services. The Company recognizes revenue from Pattern ratably over the term of the subscription. The Pattern subscription fee is $15 per month and is nonrefundable. Other revenue : Other revenue typically includes revenue generated from commercial partnerships, which are recognized as the customer in each contract consumes the benefit of the service Etsy provides in each arrangement. Payment terms Etsy sellers receive a bill electronically on the first day of each month for the previous month’s charges, including all listing fees, transactions fees, Promoted Listing fees, Etsy Shipping Labels fees, and Pattern fees. Payment is due by the 15th of every month. Etsy Payments fees are deducted from the funds credited to the seller's shop payment account prior to settlement of those funds to the seller’s bank account. Contract balances Deferred revenues The Company records deferred revenues when cash payments are received or due in advance of the completion of the listing period, which represents the value of the Company's unsatisfied performance obligations. Deferred listing revenue is recognized ratably over the remainder of the four month listing period, unless the item is sold or the seller relists it, at which time any remaining listing fee is recognized. The following table summarizes the deferred revenue activity during the period indicated (in thousands): Three Months Ended 2018 Balance as of the beginning of the period $ 6,262 Cash payments received or due 18,151 Revenue recognized in the period (17,949 ) Balance as of the end of the period $ 6,464 Significant Judgments Judgment is required to assess the nature of the services that the Company promises to its customers and the timing of satisfaction of those promised services. For services that are refundable, the Company accounts for the right of return as a refund liability and reduction of revenue recognized in the amount of refunds that are expected to be issued. Refunds are estimated monthly, are based on historical refund patterns, and are updated at the end of each reporting period as additional information becomes available.

Convertible Debt

Convertible Debt	3 Months Ended
	Mar. 31, 2018
Debt Disclosure [Abstract]
Convertible Debt	Note 3—Convertible Debt In March 2018 , the Company issued $345.0 million aggregate principal amount of 0% Convertible Senior Notes due 2023 (the “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 Notes were $334.9 million after deducting the initial purchasers' discount and offering expenses. The Notes are convertible based upon an initial conversion rate of 27.5691 shares of the Company’s common stock per $1,000 principal amount of Notes (equivalent to an initial conversion price of approximately $36.27 per share). The conversion rate will be subject to adjustment upon the occurrence of certain specified events, including certain distributions and dividends to all or substantially all of the holders of the Company’s common stock. The Company will settle any conversions of the Notes in cash, shares of the Company’s common stock or a combination thereof, with the form of consideration determined at the Company’s election. The Notes will mature on March 1, 2023 , unless earlier converted or repurchased. Prior to the close of business on the business day immediately preceding November 1, 2022 , holders may convert all or a portion of their Notes only under the following circumstances: (1) during any calendar quarter commencing after the calendar quarter ending on June 30, 2018 (and only during such calendar quarter), if the last reported sale price of the Company’s common stock for at least 20 trading days (whether or not consecutive) during a period of 30 consecutive trading days ending on, and including, the last trading day of the immediately preceding calendar quarter is greater than or equal to 130% of the conversion price on each applicable trading day; (2) during the 5 business day period after any 10 consecutive trading day period (the “measurement period”) in which the trading price per $1,000 principal amount of Notes for each trading day of the measurement period was less than 98% of the product of the last reported sale price of the Company’s common stock and the conversion rate on each such trading day; (3) with respect to any or all of the Notes called for redemption by the Company prior to the close of business on the business day immediately preceding November 1, 2022 , holders may convert all or any portion of their notes at any time prior to the close of business on the second scheduled trading day prior to the redemption date, even if the notes are not otherwise convertible at such time; (4) upon the occurrence of specified corporate events. On and after November 1, 2022 until the close of business on the second scheduled trading day immediately preceding the maturity date, holders may convert their Notes at any time, regardless of the foregoing circumstances. If a fundamental change occurs prior to the maturity date, holders may require the Company to repurchase all or a portion of their Notes for cash at a price equal to 100% of the principal amount of the Notes to be repurchased. Holders of Notes who convert their Notes in connection with a notice of a redemption or a make-whole fundamental change may be entitled to a premium in the form of an increase in the conversion rate of the Notes. As of March 31, 2018 , none of the conditions permitting the holders of the Notes to early convert had been met. Therefore the Notes are classified as long-term debt. The Notes are general unsecured obligations of the Company. The 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; equal in right of payment with all of our liabilities that are not so subordinated; 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. In accounting for the issuance of the Notes, the Company separated the Notes into liability and equity components. The carrying amount of the liability component was calculated by measuring the fair value of a similar liability that does not have an associated convertible feature. The carrying amount of the equity component, representing the conversion option, which does not meet the criteria for separate accounting as a derivative as it is indexed to the Company's own stock, was determined by deducting the fair value of the liability component from the par value of the Notes. The difference between the principal amount of the Notes and the liability component represents the debt discount, which is recorded as a direct deduction from the related debt liability in the Consolidated Balance Sheet and accreted over the period from the date of issuance to the contractual maturity date, resulting in the recognition of non-cash interest expense. The equity component of the Notes of approximately $72.8 million is included in additional paid-in capital in the Consolidated Balance Sheet and is not remeasured as long as it continues to meet the conditions for equity classification. Transaction costs were allocated to the liability and equity components in the same proportion as the allocation of the proceeds. Transaction costs attributable to the liability component were recorded as a direct deduction from the related debt liability in the Consolidated Balance Sheet and are amortized to interest expense using the effective interest method over the term of the Notes, and transaction costs attributable to the equity component were netted with the equity component in stockholders’ equity. Non-cash interest expense related to the Notes for the period ended March 31, 2018 was $1.2 million . The estimated fair value of the Notes was $272.2 million as of March 31, 2018 . The estimated fair value of the Notes was determined through consideration of quoted market prices for similar instruments. The fair value is classified as Level 2, as defined in “ Note 7—Fair Value Measurements .” Capped Call Transactions The Company used $34.2 million of the net proceeds from the Notes offering to enter into separate capped call transactions (“Capped Call Transactions”) with the initial purchasers and/or their respective affiliates. The Capped Call Transactions are expected generally to reduce the potential dilution and/or offset the cash payments the Company is required to make in excess of the principal amount of the Notes upon conversion of the Notes in the event that the market price per share of the Company’s common stock is greater than the strike price of the Capped Call Transactions with such reduction and/or offset subject to a cap. The Capped Call Transactions have an initial cap price of $52.76 per share of the Company’s common stock, which represents a premium of 100% over the last reported sale price of the Company’s common stock on March 8, 2018 , and is subject to certain adjustments under the terms of the Capped Call Transactions. Collectively, the Capped Call Transactions cover, initially, the number of shares of the Company’s common stock underlying the Notes, subject to anti-dilution adjustments substantially similar to those applicable to the Notes. The Capped Call Transactions do not meet the criteria for separate accounting as a derivative as they are indexed to the Company's stock. The premiums paid for the Capped Call Transactions have been included as a net reduction to additional paid-in capital within stockholders’ equity.

Stock-based Compensation

Stock-based Compensation	3 Months Ended
	Mar. 31, 2018
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Stock-based Compensation	Note 4—Stock-based Compensation During the three months ended March 31, 2018 , the Company granted stock options and restricted stock units (“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 6,088,461 shares to the total number of shares available for issuance under the 2015 Plan effective as of January 2, 2018. At March 31, 2018 , 29,436,374 shares were authorized under the 2015 Plan and 18,316,257 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 2018 2017 Volatility 41.9% - 42.1% 42.2% - 42.7% Risk-free interest rate 2.6% - 2.7% 2.1% - 2.2% Expected term (in years) 5.98 - 6.25 6.25 Dividend rate —% —% The following table summarizes the activity for the Company's options during the three months ended March 31, 2018 (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, 2017 7,947,939 $ 11.02 Granted 622,476 26.76 Exercised (887,906 ) 11.54 Forfeited/Canceled (108,541 ) 13.85 Outstanding at March 31, 2018 7,573,968 12.27 8.50 $ 119,764 Total exercisable at March 31, 2018 1,551,029 9.95 6.21 28,082 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, 2018 and 2017 (in thousands except per share amounts): Three Months Ended 2018 2017 Weighted-average grant date fair value of options granted $ 12.31 $ 4.66 Intrinsic value of options exercised 9,799 1,732 Fair value of awards vested 2,930 3,790 The total unrecognized compensation expense at March 31, 2018 related to the Company's options was $28.5 million , which will be recognized over an estimated weighted-average amortization period of 3.30 years. The following table summarizes the activity for the Company's unvested RSUs during the three months ended March 31, 2018 : Shares Weighted-Average Unvested at December 31, 2017 3,074,247 $ 11.98 Granted 1,824,704 27.00 Vested (191,925 ) 11.04 Forfeited/Canceled (123,980 ) 12.15 Unvested at March 31, 2018 4,583,046 17.99 The total unrecognized compensation expense at March 31, 2018 related to the Company's unvested RSUs was $73.3 million , which will be recognized over an estimated weighted-average amortization period of 3.54 years. Total stock-based compensation expense included in the Consolidated Statements of Operations for the periods presented below is as follows (in thousands): Three Months Ended 2018 2017 Cost of revenue $ 546 $ 364 Marketing 478 444 Product development 2,639 2,020 General and administrative 2,791 2,057 Total stock-based compensation expense $ 6,454 $ 4,885 Total stock-based compensation expense in the three months ended March 31, 2018 and 2017 includes $0.7 million and $0.8 million in acquisition-related stock-based compensation expense, respectively.

Stockholders' Equity

Stockholders' Equity	3 Months Ended
	Mar. 31, 2018
Equity [Abstract]
Stockholders' Equity	Note 5—Stockholders’ Equity In November 2017, the Board of Directors approved a stock repurchase program that enables the Company to repurchase up to $100 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 may 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 share repurchase activity, excluding shares withheld to satisfy tax withholding obligations in connection with the vesting of employee restricted stock units (in thousands except share and per share amounts): Shares Repurchased Average Price Paid per Share (1) Value of Shares Repurchased Remaining Amount Authorized Balance as of December 31, 2017 586,231 $ 17.57 $ 10,301 $ 89,699 Repurchases of common stock for the three months ended: March 31, 2018 2,807,393 24.43 68,586 (68,586 ) Balance as of March 31, 2018 3,393,624 $ 23.25 $ 78,887 $ 21,113 (1) Average price paid per share excludes broker commissions. All repurchased shares of common stock have been retired.

Income Taxes

Income Taxes	3 Months Ended
	Mar. 31, 2018
Income Tax Disclosure [Abstract]
Income Taxes	Note 6—Income Taxes On December 22, 2017, the U.S. government enacted The Tax Cuts and Jobs Act (“The Act”) which includes significant changes to the taxation of business entities. These changes include, among others, (1) a permanent reduction to the corporate income tax rate, (2) a partial limitation on the deductibility of business interest expense (“163(j) Interest Limitation”), and (3) a shift of the U.S. taxation of multinational corporations from a tax on worldwide income to a quasiterritorial system (along with certain rules designed to prevent erosion of the U.S. income tax base). Effective January 1, 2018, the Company is subject to several provisions of the Tax Act including computations under Global Intangible Low Taxed Income (“GILTI”), Foreign Derived Intangible Income (“FDII”), Base Erosion and Anti-Abuse Tax (“BEAT”), and the 163(j) Interest Limitation. For the GILTI and FDII computations, the Company recorded a reasonable estimate in its annual effective tax rate as of March 31, 2018. For the BEAT and 163(j) Interest Limitation computations, the Company did not record an estimate in its effective tax rate for the three months ended March 31, 2018 because the Company currently estimates that these provisions of The Act will not apply in 2018. The Company will continue to refine the estimates for the computations of the GILTI, FDII, BEAT and the 163(j) Interest Limitation rules as it gathers additional information during the year. The Company also continues to evaluate the impact of the GILTI provisions under The Act which are complex and subject to continuing regulatory interpretation by the IRS. The Company is required to make an accounting policy election of either (1) treating taxes due on future U.S. inclusions in taxable income related to GILTI as a current period expense when incurred (the “period cost method”) or (2) factoring such amounts into the Company’s measurement of its deferred taxes (the “deferred method”). The Company’s accounting policy election with respect to the new GILTI rules will depend, in part, on analyzing its global income to determine whether it can reasonably estimate the tax impact. While the Company has included an estimate of GILTI in its estimated effective tax rate for 2018, it has not completed its analysis and is not yet able to determine which method to elect. Adjustments related to the amount of GILTI recorded in its Consolidated Financial Statements may be required based on the outcome of this election. The amount of unrecognized tax benefits included in the Consolidated Balance Sheets remained flat at $17.0 million as of March 31, 2018 and December 31, 2017 . The total amount of unrecognized tax benefits that, if recognized, would favorably affect the effective tax rate is $17.0 million at March 31, 2018 .

Fair Value Measurements

Fair Value Measurements	3 Months Ended
	Mar. 31, 2018
Fair Value Disclosures [Abstract]
Fair Value Measurements	Note 7—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 Sheet 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 March 31, 2018 and December 31, 2017 (in thousands): As of March 31, 2018 Level 1 Level 2 Level 3 Total Assets Cash equivalents: Commercial paper $ — $ 6,987 $ — $ 6,987 Money market funds 444,041 — — 444,041 444,041 6,987 — 451,028 Short-term investments: Commercial paper — 32,952 — 32,952 Corporate bonds — 24,629 — 24,629 U.S. Government and agency securities 9,945 — — 9,945 9,945 57,581 — 67,526 Funds receivable and seller accounts: Money market funds 20,071 — — 20,071 20,071 — — 20,071 $ 474,057 $ 64,568 $ — $ 538,625 As of December 31, 2017 Level 1 Level 2 Level 3 Total Assets Cash equivalents: Commercial paper $ — $ 11,290 $ — $ 11,290 Money market funds 204,867 — — 204,867 U.S. Government and agency securities 24,989 — — 24,989 229,856 11,290 — 241,146 Short-term investments: Commercial paper — 2,998 — 2,998 Corporate bonds — 12,748 — 12,748 U.S. Government and agency securities 9,362 — — 9,362 9,362 15,746 — 25,108 Funds receivable and seller accounts: Money market funds 14,144 — — 14,144 14,144 — — 14,144 $ 253,362 $ 27,036 $ — $ 280,398 Level 1 instruments include investments in debt securities including money market funds and AA-rated 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 and corporate bonds, 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, 2018 and December 31, 2017 . See “ Note 8—Marketable Securities ” for additional information on the Company's marketable securities measured at fair value. Disclosure of Fair Values Our financial instruments that are not remeasured at fair value include the Notes (see “ Note 3—Convertible Debt ”). The Company estimates the fair value of the Notes through consideration of quoted market prices of similar instruments, classified as Level 2 as described above. The following table presents the estimated fair values and the carrying values (in thousands): As of March 31, 2018 As of December 31, 2017 Carrying Value Fair Value Carrying Value Fair Value Long term debt $ 265,415 $ 272,194 $ — $ —

Marketable Securities

Marketable Securities	3 Months Ended
	Mar. 31, 2018
Investments, Debt and Equity Securities [Abstract]
Marketable Securities	Note 8—Marketable Securities Short-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, 2018 Cash equivalents: Commercial paper $ 6,987 $ — $ — $ 6,987 6,987 — — 6,987 Short-term investments: Commercial paper 32,952 — — 32,952 Corporate bonds 24,658 (29 ) — 24,629 U.S. Government and agency securities 9,950 (5 ) — 9,945 67,560 (34 ) — 67,526 $ 74,547 $ (34 ) $ — $ 74,513 December 31, 2017 Cash equivalents: Commercial paper $ 11,290 $ — $ — $ 11,290 U.S. Government and agency securities 24,990 (1 ) — 24,989 36,280 (1 ) — 36,279 Short-term investments: Commercial paper 2,998 — — 2,998 Corporate bonds 12,754 (6 ) — 12,748 U.S. Government and agency securities 9,352 (1 ) 11 9,362 25,104 (7 ) 11 25,108 $ 61,384 $ (8 ) $ 11 $ 61,387 The Company’s investments in marketable securities consist primarily of investments in debt securities, including AA-rated U.S. Government and agency securities and fixed-income funds. When evaluating investments for other-than-temporary impairment, the Company reviews factors such as length of time and extent to which fair value has been below cost basis, the financial condition of the issuer and the Company’s ability, and intent to hold the investment for a period of time, which may be sufficient for anticipated recovery in market value. The Company evaluates fair values for each individual security in the investment portfolio. See “ Note 7—Fair Value Measurements ” for additional information on the Company's marketable securities measured at fair value.

Net Income (Loss) Per Share

Net Income (Loss) Per Share	3 Months Ended
	Mar. 31, 2018
Earnings Per Share [Abstract]
Net Income (Loss) Per Share	Note 9— Net Income (Loss) Per Share The following table presents the calculation of basic and diluted net income (loss) per share for periods presented (in thousands except share and per share amounts): Three Months Ended 2018 2017 Numerator: Net inco me (loss) $ 12,967 $ (421 ) Net income allocated to participating securities under the two-class method (13 ) — Net inco me (loss) applicable to common sto ckholders—basic 12,954 (421 ) Dilutive effect of net income allocated to participating securities under the two-class method 13 — Net income (loss) attributable to common stockholders—diluted $ 12,967 $ (421 ) Denominator: Weighted-average common shares outstanding—basic (1) 121,267,092 115,696,024 Common equivalent shares from options to purchase common stock and restricted stock units 2,836,429 — Dilutive effect of assumed conversion of restricted stock units 1,608,854 — Dilutive effect of assumed conversion of restricted stock from acquisition 59,940 — Weighted-average common shares outstanding—diluted 125,772,315 115,696,024 Net inco me (loss) per share attributable to common stockho lders—basic $ 0.11 $ 0.00 Net income (loss) per shar e attributable to common stockholders—dilute d $ 0.10 $ 0.00 (1) 114,963 shares of unvested stock are considered participating securities and are excluded from basic shares outstanding for the three months ended March 31, 2018 . The following potential common shares were excluded from the calculation of diluted net income (loss) per share attributable to common stockholders because their effect would have been anti-dilutive for the periods presented: Three Months Ended 2018 2017 Stock options 225,099 9,543,393 Restricted stock units 428,846 3,547,176 Total anti-dilutive securities 653,945 13,090,569

Segment and Geographic Informat

Segment and Geographic Information	3 Months Ended
	Mar. 31, 2018
Segment Reporting [Abstract]
Segment and Geographic Information	Note 10—Segment and Geographic Information The Company has determined it operates as one operating and reportable segment for purposes of allocating resources and evaluating financial performance. Revenue by country is based on the billing address of the seller. The following table summarizes revenue, income (loss) before income taxes and net income (loss) by geographic area for the periods presented (in thousands): Three Months Ended 2018 2017 United States $ 84,923 $ 71,523 International 35,989 25,368 Revenue $ 120,912 $ 96,891 United States $ (1,200 ) $ (9,603 ) International 14,181 8,130 Income (loss) before income taxes $ 12,981 $ (1,473 ) United States $ (953 ) $ (8,326 ) International 13,920 7,905 Net inco me (loss) $ 12,967 $ (421 ) No individual country’s revenue other than the United States exceeded 10% of total revenue for the periods presented. All significant long-lived assets are located in the United States.

Commitments and Contingencies

Commitments and Contingencies	3 Months Ended
	Mar. 31, 2018
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	Note 11—Commitments and Contingencies Long-Term Debt In March 2018 , the Company issued $345.0 million aggregate principal amount of 0% Convertible Senior Notes due 2023 (the “Notes”) in a private placement to qualified institutional buyers pursuant to Rule 144A under the Securities Act. The Notes will mature on March 1, 2023 , unless earlier converted or repurchased, and there are no contractual payments required until maturity. For more information on the Notes, see “ Note 3—Convertible Debt ”. Non-Income Tax Contingencies The Company had reserves of $2.3 million and $0.4 million at March 31, 2018 and December 31, 2017 , respectively, for certain non-income tax obligations, representing management’s best estimate of its probable liability. The Company could also be subject to examination in various jurisdictions related to non-income tax matters. The resolution of these types of matters, if in excess of the recorded reserve, could have an adverse impact on the Company’s business. Legal Proceedings Altayyar Case On May 13, 2015, a purported securities class action complaint ( Altayyar v. Etsy, Inc., et al. , Docket No. 1:15-cv-02785) was filed in the United States District Court for the Eastern District of New York against the Company and certain officers. The complaint was brought on behalf of a purported class consisting of all persons or entities who purchased or otherwise acquired shares of the Company's common stock from April 16, 2015 through and including May 10, 2015. It asserted violations of Sections 10(b) and 20(a) of the Securities Exchange Act of 1934 based on allegedly false or misleading statements and omissions with respect to, among other things, merchandise for sale on the Company's website that may be counterfeit or constitute trademark or copyright infringement and actions taken by third-party brands against Etsy sellers for trademark or copyright infringement. On October 22, 2015, the court appointed a lead plaintiff and lead plaintiff’s counsel. On January 21, 2016, the lead plaintiff filed an amended class action complaint alleging false or misleading statements or omissions with respect to substantially the same topics as the original complaint. The amended complaint adds certain outside directors and underwriters as defendants, expanded the purported class period to be April 16, 2015 to August 4, 2015, inclusive, and asserted violations of Sections 11, 12(a)(2), and 15 of the Securities Act of 1933, as well as Sections 10(b) and 20(a) of the Securities Exchange Act of 1934, as amended (the “Exchange Act”). The amended complaint sought certification as a class action and unspecified compensatory damages plus interest and attorneys' fees. On April 5, 2016, defendants moved to dismiss the amended complaint. On March 24, 2017, the court entered a judgment dismissing the amended complaint in its entirety, with prejudice, based on an opinion filed March 16, 2017. On August 2, 2017, Plaintiffs appealed to the United States Court of Appeals for the Second Circuit. On April 24, 2018, the Second Circuit affirmed the judgment of the District Court. Cervantes and Weiss Cases On July 21, 2015, a purported securities class action complaint ( Cervantes v. Dickerson, et.al ., Case No. CIV 534768) was filed in the Superior Court of State of California, County of San Mateo against the Company, certain officers, directors, and underwriters. The complaint asserts violations of Sections 11 and 15 of the Securities Act of 1933. As in the Altayyar litigation, the complaint alleges misrepresentations in the Company’s Registration Statement on Form S-1 and Prospectus with respect to, among other things, merchandise for sale on the Company's website that may be counterfeit or constitute trademark or copyright infringement. The complaint seeks certification as a class action and unspecified compensatory damages plus interest and attorneys' fees. On December 7, 2015, the Company and the underwriter defendants moved to stay the Cervantes action on the grounds of forum non conveniens. On November 5, 2015, another purported securities class action complaint ( Weiss v. Etsy et al. , No. CIV 536123) was filed in the Superior Court of State of California, County of San Mateo. The Weiss complaint names as defendants the Company and the same officers, directors, and underwriters named in the Cervantes complaint, and also asserts violations of Sections 11 and 15 of the Securities Act of 1933 based on allegedly false or misleading statements or omissions with respect to, among other things, merchandise for sale on the Company's website that may be counterfeit or constitute trademark or copyright infringement. On December 24, 2015, the court consolidated the Cervantes and Weiss actions. The Company and the named officers and directors intend to defend themselves vigorously against these consolidated actions. In light of, among other things, the early stage of the litigation, the Company is unable to predict the outcome of this matter and is unable to make a meaningful estimate of the amount or range of loss, if any, that could result from an unfavorable outcome. On February 3, 2016, the court granted the Company’s motion to stay the consolidated actions. In addition, 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 Consolidated Results of Operations or Cash Flows in the period the claims or litigation are resolved. Although the results of litigation and claims cannot be predicted with certainty, we currently believe that the final outcome of these ordinary course matters will not have a material adverse effect on our business.

Restructuring and Other Exit Co

Restructuring and Other Exit Costs	3 Months Ended
	Mar. 31, 2018
Restructuring and Related Activities [Abstract]
Restructuring and Other Exit Costs	Note 12—Restructuring and Other Exit Costs On April 30, 2017, the Board of Directors approved a plan to increase efficiency and streamline the Company's cost structure through headcount reductions and a reduction in internal program expenses (the “May Actions”). On June 16, 2017, the Board of Directors approved additional initiatives that are designed to improve focus on key strategic growth opportunities (together with the May Actions, the “Actions”). The Actions included total headcount reductions of 245 positions or 23% of the total workforce as of December 31, 2017 , closing A Little Market (“ALM”), a market in France, and closing or consolidating certain international offices. In connection with the Actions, the Company incurred $13.9 million of restructuring and other exit costs in the year ended December 31, 2017 , comprised of employee severance, stock compensation modifications, and other exit costs, largely made up of cash expenditures. The Company generated $0.2 million of income in the three months ended March 31, 2018 due to changes in estimated severance costs. All remaining cash payments are expected to be recognized in 2018. The following table displays restructuring and other exit costs (income) recorded related to the Actions and a rollforward of the charges to the accrued expenses balance as of March 31, 2018 (in thousands): Severance Charge Stock-Based Compensation Other Exit Costs Total Balance, December 31, 2017 $ 1,308 $ — $ 34 $ 1,342 Total restructuring and other exit costs (income) (156 ) — 5 (151 ) Costs charged against equity/assets — — — — Cash payments (793 ) — — (793 ) Balance, March 31, 2018 $ 359 $ — $ 39 $ 398 Total restructuring and other exit costs (income) related to the Actions included in the Consolidated Statements of Operations are as follows (in thousands): Three Months Ended 2018 2017 Cost of revenue $ (7 ) $ — Marketing (58 ) — Product development (79 ) — General and administrative (7 ) — Total restructuring and other exit costs (income) $ (151 ) $ —

Basis of Presentation and Sum20

Basis of Presentation and Summary of Significant Accounting Policies (Policies)	3 Months Ended
	Mar. 31, 2018
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.
Reclassifications	Reclassifications Certain items in the prior years’ Consolidated Financial Statements have been reclassified to conform to the current year presentation reflected in the Consolidated Financial Statements. Specifically, the Company reclassified $29.8 million previously included in Services revenue to Marketplace revenue (see “ Note 2—Revenue ”) for the the three months ended March 31, 2017 to conform to the current year presentation in connection with the adoption of Accounting Standards Codification (“ASC”) 606, Revenue from Contracts with Customers .
Use of Estimates	Use of Estimates The preparation of the Company’s Consolidated Financial Statements in conformity with accounting principles generally accepted in the United States of America (“GAAP”) requires management to make estimates and judgments that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of revenues and expenses during the reporting period. The accounting estimates that require management’s most difficult and subjective judgments include: for revenue recognition, determining the nature and timing of satisfaction of performance obligations; income taxes; website development costs and internal-use software; purchase price allocations for business combinations; valuation of goodwill and intangible assets; leases; stock-based compensation; restructuring and other exit costs (income); and fair value of financial instruments. The Company evaluates its estimates and judgments on an ongoing basis and revises them when necessary. Actual results may differ from the original or revised estimates.
Revenue Recognition	Revenue Recognition The Company’s revenue is diversified; generated from a mix of marketplace activities and other optional services to help Etsy sellers start, manage and scale their business. Revenues are recognized as the Company transfers control of promised goods or services to Etsy sellers, in an amount that reflects the consideration the Company expects to be entitled to in exchange for those goods or services. The Company evaluates whether it is appropriate to recognize revenue on a gross or net basis based upon its evaluation of whether the Company obtains control of the specified goods or services by considering if it is primarily responsible for fulfillment of the promise, has inventory risk and has the latitude in establishing pricing and selecting suppliers, among other factors. Based on its evaluation of these factors, revenue is recorded either gross or net of costs associated with the transaction. Sales and usage-based taxes are excluded from revenues.
Income Tax	Income Taxes The Company's income tax (provision) benefit for interim periods is determined using an estimate of its annual effective tax rate adjusted for discrete items, if any, for relevant interim periods. The Company updates its estimate of the annual effective tax rate each quarter and makes cumulative adjustments if its estimated annual tax rate changes. The Company's quarterly tax provision and quarterly estimate of its annual effective tax rate are subject to significant variations due to several factors, including variability in predicting its pretax and taxable income and the mix of jurisdictions to which those relate, changes of expenses or losses for which tax benefits are not recognized, recording of excess tax benefits related to stock-based compensation and changes in the laws, regulations and administrative practices of the jurisdictions in which the Company operates.
Net Income (Loss) Per Share	Net Income (Loss) Per Share Basic net income (loss) per share attributable to common stockholders is computed by dividing the net income (loss) attributable to common stockholders by the weighted-average number of common shares outstanding for the period. Diluted net income (loss) per share is computed by dividing net income (loss) for the period by the weighted-average number of shares of common stock and potentially dilutive common stock outstanding during the period. The dilutive effect of outstanding options and stock-based compensation awards is reflected in diluted net income (loss) per share by application of the treasury stock method. Since the Company expects to settle in cash the principal outstanding under the 0% Convertible Senior Notes due 2023 the Company issued in March 2018 (the “Notes,” see “ Note 3—Convertible Debt ”) it uses the treasury stock method when calculating their potential dilutive effect of the conversion spread on diluted net income per share, if applicable. The conversion spread will have a dilutive impact on diluted net income per share of common stock when the average market price of the Company's common stock for a given period exceeds the conversion price of $36.27 per share. The calculation of diluted net income (loss) per share excludes all anti-dilutive common shares. For periods in which the Company has reported net losses, diluted net loss per share attributable to common stockholders is the same as basic net loss per share attributable to common stockholders, because dilutive common shares are not assumed to have been issued if their effect is anti-dilutive.
Recently Issued and Recently Adopted Accounting Pronouncements	Recently Issued Accounting Pronouncements In February 2016, the Financial Accounting Standards Board (“FASB”) issued ASU 2016-02, Leases , and additional changes, modifications, clarifications or interpretations related to this guidance thereafter, which require a reporting entity to recognize right-of-use assets and lease liabilities on the balance sheet for operating leases to increase transparency and comparability. The new guidance is effective for annual and interim periods beginning after December 15, 2018, and early adoption is permitted. Upon adoption of this standard, the Company expects to recognize, on a discounted basis, its minimum commitments under noncancelable operating leases on the Consolidated Balance Sheets resulting in the recording of right-of-use assets and lease obligations. The Company is currently evaluating whether there are any additional impacts this guidance will have on its Consolidated Financial Statements. Recently Adopted Accounting Pronouncements In May 2014, the FASB issued ASU 2014-09, Revenue from Contracts with Customers , and additional changes, modifications, clarifications or interpretations related to this guidance thereafter, which replaces existing revenue recognition guidance. The new guidance is effective for the annual and interim periods beginning after December 15, 2017. Among other things, the updated guidance requires companies to recognize revenue in a way that depicts the transfer of promised goods or services to customers in an amount that reflects the consideration to which the entity expects to be entitled in exchange for those goods or services. The Company adopted the requirements of the new guidance as of January 1, 2018, utilizing the full retrospective method of transition. Adoption of the new guidance did not result in changes to the prior year or current year Consolidated Financial Statements. See “ Note 2—Revenue ” for additional information regarding revenue recognition. In November 2016, the FASB issued ASU 2016-18, Statement of Cash Flows: Restricted Cash , which requires that a statement of cash flows explain the change during the period in the total of cash, cash equivalents and amounts generally described as restricted cash or restricted cash equivalents. The new guidance is effective for the annual and interim periods beginning after December 15, 2017. The Company adopted this standard in the first quarter of 2018 utilizing the full retrospective method of transition. As a result of this guidance, the Company reclassified $5.3 million on the Consolidated Statement of Cash Flows in the three months ended March 31, 2018 and 2017 to include restricted cash in the beginning and ending cash, cash equivalent and restricted cash balances. The following table provides a reconciliation of cash, cash equivalents and restricted cash reported within the Consolidated Balance Sheets that sum to the total of the same such amounts shown in the Consolidated Statement of Cash Flows (in thousands): Three Months Ended March 31, 2018 2017 Beginning balance: Cash and cash equivalents $ 315,442 $ 181,592 Restricted cash 5,341 5,341 Total cash, cash equivalents and restricted cash $ 320,783 $ 186,933 Ending balance: Cash and cash equivalents $ 533,855 $ 194,807 Restricted cash 5,341 5,341 Total cash, cash equivalents and restricted cash $ 539,196 $ 200,148 The balances included in restricted cash represent amounts held as collateral associated with the lease of the Company's Brooklyn, New York headquarters. This standard had no other impact to the Consolidated Financial Statements.

Basis of Presentation and Sum21

Basis of Presentation and Summary of Significant Accounting Policies (Tables)	3 Months Ended
	Mar. 31, 2018
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Schedule of New Accounting Pronouncements and Changes in Accounting Principles	The following table provides a reconciliation of cash, cash equivalents and restricted cash reported within the Consolidated Balance Sheets that sum to the total of the same such amounts shown in the Consolidated Statement of Cash Flows (in thousands): Three Months Ended March 31, 2018 2017 Beginning balance: Cash and cash equivalents $ 315,442 $ 181,592 Restricted cash 5,341 5,341 Total cash, cash equivalents and restricted cash $ 320,783 $ 186,933 Ending balance: Cash and cash equivalents $ 533,855 $ 194,807 Restricted cash 5,341 5,341 Total cash, cash equivalents and restricted cash $ 539,196 $ 200,148

Revenue (Tables)

Revenue (Tables)	3 Months Ended
	Mar. 31, 2018
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 2018 2017 Marketplace revenue (1) $ 87,967 $ 70,562 Services revenue 32,605 24,144 Other revenue 340 2,185 Revenue $ 120,912 $ 96,891 (1) Etsy Payments revenue for the three months ended March 31, 2018 has been classified and presented within Marketplace revenue. Comparative periods have been reclassified to conform to current period presentation.
Deferred Revenue, by Arrangement, Disclosure	The following table summarizes the deferred revenue activity during the period indicated (in thousands): Three Months Ended 2018 Balance as of the beginning of the period $ 6,262 Cash payments received or due 18,151 Revenue recognized in the period (17,949 ) Balance as of the end of the period $ 6,464

Stock-based Compensation (Table

Stock-based Compensation (Tables)	3 Months Ended
	Mar. 31, 2018
Disclosure of Compensation Related Costs, Share-based Payments [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 2018 2017 Volatility 41.9% - 42.1% 42.2% - 42.7% Risk-free interest rate 2.6% - 2.7% 2.1% - 2.2% Expected term (in years) 5.98 - 6.25 6.25 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, 2018 (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, 2017 7,947,939 $ 11.02 Granted 622,476 26.76 Exercised (887,906 ) 11.54 Forfeited/Canceled (108,541 ) 13.85 Outstanding at March 31, 2018 7,573,968 12.27 8.50 $ 119,764 Total exercisable at March 31, 2018 1,551,029 9.95 6.21 28,082
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, 2018 and 2017 (in thousands except per share amounts): Three Months Ended 2018 2017 Weighted-average grant date fair value of options granted $ 12.31 $ 4.66 Intrinsic value of options exercised 9,799 1,732 Fair value of awards vested 2,930 3,790
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, 2018 and 2017 (in thousands except per share amounts): Three Months Ended 2018 2017 Weighted-average grant date fair value of options granted $ 12.31 $ 4.66 Intrinsic value of options exercised 9,799 1,732 Fair value of awards vested 2,930 3,790
Summary of Unvested RSU Activity	The following table summarizes the activity for the Company's unvested RSUs during the three months ended March 31, 2018 : Shares Weighted-Average Unvested at December 31, 2017 3,074,247 $ 11.98 Granted 1,824,704 27.00 Vested (191,925 ) 11.04 Forfeited/Canceled (123,980 ) 12.15 Unvested at March 31, 2018 4,583,046 17.99
Schedule of Stock-Based Compensation Expense	Total stock-based compensation expense included in the Consolidated Statements of Operations for the periods presented below is as follows (in thousands): Three Months Ended 2018 2017 Cost of revenue $ 546 $ 364 Marketing 478 444 Product development 2,639 2,020 General and administrative 2,791 2,057 Total stock-based compensation expense $ 6,454 $ 4,885

Stockholders' Equity (Tables)

Stockholders' Equity (Tables)	3 Months Ended
	Mar. 31, 2018
Equity [Abstract]
Class of Treasury Stock	The following table summarizes the Company's share repurchase activity, excluding shares withheld to satisfy tax withholding obligations in connection with the vesting of employee restricted stock units (in thousands except share and per share amounts): Shares Repurchased Average Price Paid per Share (1) Value of Shares Repurchased Remaining Amount Authorized Balance as of December 31, 2017 586,231 $ 17.57 $ 10,301 $ 89,699 Repurchases of common stock for the three months ended: March 31, 2018 2,807,393 24.43 68,586 (68,586 ) Balance as of March 31, 2018 3,393,624 $ 23.25 $ 78,887 $ 21,113 (1) Average price paid per share excludes broker commissions.

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	3 Months Ended
	Mar. 31, 2018
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 March 31, 2018 and December 31, 2017 (in thousands): As of March 31, 2018 Level 1 Level 2 Level 3 Total Assets Cash equivalents: Commercial paper $ — $ 6,987 $ — $ 6,987 Money market funds 444,041 — — 444,041 444,041 6,987 — 451,028 Short-term investments: Commercial paper — 32,952 — 32,952 Corporate bonds — 24,629 — 24,629 U.S. Government and agency securities 9,945 — — 9,945 9,945 57,581 — 67,526 Funds receivable and seller accounts: Money market funds 20,071 — — 20,071 20,071 — — 20,071 $ 474,057 $ 64,568 $ — $ 538,625 As of December 31, 2017 Level 1 Level 2 Level 3 Total Assets Cash equivalents: Commercial paper $ — $ 11,290 $ — $ 11,290 Money market funds 204,867 — — 204,867 U.S. Government and agency securities 24,989 — — 24,989 229,856 11,290 — 241,146 Short-term investments: Commercial paper — 2,998 — 2,998 Corporate bonds — 12,748 — 12,748 U.S. Government and agency securities 9,362 — — 9,362 9,362 15,746 — 25,108 Funds receivable and seller accounts: Money market funds 14,144 — — 14,144 14,144 — — 14,144 $ 253,362 $ 27,036 $ — $ 280,398
Schedule of Carrying Values and Estimated Fair Values of Debt Instruments	The following table presents the estimated fair values and the carrying values (in thousands): As of March 31, 2018 As of December 31, 2017 Carrying Value Fair Value Carrying Value Fair Value Long term debt $ 265,415 $ 272,194 $ — $ —

Marketable Securities (Tables)

Marketable Securities (Tables)	3 Months Ended
	Mar. 31, 2018
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, 2018 Cash equivalents: Commercial paper $ 6,987 $ — $ — $ 6,987 6,987 — — 6,987 Short-term investments: Commercial paper 32,952 — — 32,952 Corporate bonds 24,658 (29 ) — 24,629 U.S. Government and agency securities 9,950 (5 ) — 9,945 67,560 (34 ) — 67,526 $ 74,547 $ (34 ) $ — $ 74,513 December 31, 2017 Cash equivalents: Commercial paper $ 11,290 $ — $ — $ 11,290 U.S. Government and agency securities 24,990 (1 ) — 24,989 36,280 (1 ) — 36,279 Short-term investments: Commercial paper 2,998 — — 2,998 Corporate bonds 12,754 (6 ) — 12,748 U.S. Government and agency securities 9,352 (1 ) 11 9,362 25,104 (7 ) 11 25,108 $ 61,384 $ (8 ) $ 11 $ 61,387

Net Income (Loss) Per Share (Ta

Net Income (Loss) Per Share (Tables)	3 Months Ended
	Mar. 31, 2018
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 (loss) per share for periods presented (in thousands except share and per share amounts): Three Months Ended 2018 2017 Numerator: Net inco me (loss) $ 12,967 $ (421 ) Net income allocated to participating securities under the two-class method (13 ) — Net inco me (loss) applicable to common sto ckholders—basic 12,954 (421 ) Dilutive effect of net income allocated to participating securities under the two-class method 13 — Net income (loss) attributable to common stockholders—diluted $ 12,967 $ (421 ) Denominator: Weighted-average common shares outstanding—basic (1) 121,267,092 115,696,024 Common equivalent shares from options to purchase common stock and restricted stock units 2,836,429 — Dilutive effect of assumed conversion of restricted stock units 1,608,854 — Dilutive effect of assumed conversion of restricted stock from acquisition 59,940 — Weighted-average common shares outstanding—diluted 125,772,315 115,696,024 Net inco me (loss) per share attributable to common stockho lders—basic $ 0.11 $ 0.00 Net income (loss) per shar e attributable to common stockholders—dilute d $ 0.10 $ 0.00 (1) 114,963 shares of unvested stock are considered participating securities and are excluded from basic shares outstanding for the three months ended March 31, 2018 .
Schedule of Anti-Dilutive Securities Excluded from Computation of Earnings Per Share	The following potential common shares were excluded from the calculation of diluted net income (loss) per share attributable to common stockholders because their effect would have been anti-dilutive for the periods presented: Three Months Ended 2018 2017 Stock options 225,099 9,543,393 Restricted stock units 428,846 3,547,176 Total anti-dilutive securities 653,945 13,090,569

Segment and Geographic Inform28

Segment and Geographic Information (Tables)	3 Months Ended
	Mar. 31, 2018
Segment Reporting [Abstract]
Schedule of Revenue by Geographic Area	The following table summarizes revenue, income (loss) before income taxes and net income (loss) by geographic area for the periods presented (in thousands): Three Months Ended 2018 2017 United States $ 84,923 $ 71,523 International 35,989 25,368 Revenue $ 120,912 $ 96,891 United States $ (1,200 ) $ (9,603 ) International 14,181 8,130 Income (loss) before income taxes $ 12,981 $ (1,473 ) United States $ (953 ) $ (8,326 ) International 13,920 7,905 Net inco me (loss) $ 12,967 $ (421 )

Restructuring and Other Exit 29

Restructuring and Other Exit Costs (Tables)	3 Months Ended
	Mar. 31, 2018
Restructuring and Related Activities [Abstract]
Schedule of Restructuring Reserve by Type of Cost	The following table displays restructuring and other exit costs (income) recorded related to the Actions and a rollforward of the charges to the accrued expenses balance as of March 31, 2018 (in thousands): Severance Charge Stock-Based Compensation Other Exit Costs Total Balance, December 31, 2017 $ 1,308 $ — $ 34 $ 1,342 Total restructuring and other exit costs (income) (156 ) — 5 (151 ) Costs charged against equity/assets — — — — Cash payments (793 ) — — (793 ) Balance, March 31, 2018 $ 359 $ — $ 39 $ 398
Restructuring and Related Costs	Total restructuring and other exit costs (income) related to the Actions included in the Consolidated Statements of Operations are as follows (in thousands): Three Months Ended 2018 2017 Cost of revenue $ (7 ) $ — Marketing (58 ) — Product development (79 ) — General and administrative (7 ) — Total restructuring and other exit costs (income) $ (151 ) $ —

Basis of Presentation and Sum30

Basis of Presentation and Summary of Significant Accounting Policies - Reclassifications and New Accounting Pronouncements (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017	Dec. 31, 2017	Dec. 31, 2016
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Revenues	$ 120,912	$ 96,891
Cash and cash equivalents at period start	533,855	194,807	$ 315,442	$ 181,592
Restricted cash at period start	5,341	5,341	5,341	5,341
Cash, cash equivalents and restricted cash at beginning of period	539,196	200,148	$ 320,783	$ 186,933
Restatement Adjustment | Accounting Standards Update 2016-18
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Restricted cash at period start	$ 5,300
Convertible Senior Notes due 2023
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Interest rate, stated percentage	0.00%
Marketplace Revenue | Restatement Adjustment | Accounting Standards Update 2014-09
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Revenues		$ 29,800
Convertible Debt | Convertible Senior Notes due 2023
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Conversion price	$ 36.27

Revenue (Details)

Revenue (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Disaggregation of Revenue [Line Items]
Revenue	$ 120,912	$ 96,891
Marketplace Revenue
Disaggregation of Revenue [Line Items]
Revenue	87,967	70,562
Service Revenue
Disaggregation of Revenue [Line Items]
Revenue	32,605	24,144
Other Revenue
Disaggregation of Revenue [Line Items]
Revenue	$ 340	$ 2,185

Revenue - Narrative (Details)

Revenue - Narrative (Details)	3 Months Ended
	Mar. 31, 2018USD ($)
Minimum
Revenue from External Customer [Line Items]
Foreign currency transaction fees, percent	2.50%
Maximum
Revenue from External Customer [Line Items]
Foreign currency transaction fees, percent	5.00%
Marketplace Revenue
Revenue from External Customer [Line Items]
Listing fee per item	$ 0.20
Fee for each completed transaction, percent	3.50%
Listing fee, term	4 months
Marketplace Revenue | Minimum
Revenue from External Customer [Line Items]
Etsy payment fees, percent	3.00%
Marketplace Revenue | Maximum
Revenue from External Customer [Line Items]
Etsy payment fees, percent	4.00%
Service Revenue
Revenue from External Customer [Line Items]
Subscription fee per month	$ 15

Revenue - Summary of Deferred R

Revenue - Summary of Deferred Revenue Activity (Details) $ in Thousands	3 Months Ended
	Mar. 31, 2018USD ($)
Movement in Deferred Revenue [Roll Forward]
Balance as of the beginning of the period	$ 6,262
Cash payments received or due	18,151
Revenue recognized in the period	(17,949)
Balance as of the end of the period	$ 6,464

Convertible Debt (Details)

Convertible Debt (Details)	1 Months Ended	3 Months Ended
	Mar. 31, 2018USD ($)day$ / shares	Mar. 31, 2018USD ($)$ / shares	Mar. 31, 2017USD ($)
Debt Instrument [Line Items]
Proceeds from convertible debt		$ 345,000,000	$ 0
Purchase of Capped Call Transactions		34,224,000	0
Non-cash interest expense		$ 1,077,000	$ 2,145,000
Derivative, cap price (in dollars per share) | $ / shares	$ 52.76	$ 52.76
Cap premium percentage over reported sales price		100.00%
Convertible Senior Notes due 2023
Debt Instrument [Line Items]
Interest rate, stated percentage	0.00%	0.00%
Convertible Debt | Convertible Senior Notes due 2023
Debt Instrument [Line Items]
Aggregate principle amount	$ 345,000,000	$ 345,000,000
Proceeds from convertible debt	$ 334,900,000
Conversion ratio	27.5691
Conversion price | $ / shares	$ 36.27	$ 36.27
Redemption price, percentage	100.00%
Carrying amount of equity component	$ 72,800,000	$ 72,800,000
Non-cash interest expense		1,200,000
Convertible Debt | Convertible Senior Notes due 2023 | Debt Instrument, Redemption, Period One
Debt Instrument [Line Items]
Threshold trading days | day	20
Threshold percentage of stock price trigger	130.00%
Threshold consecutive trading days | day	30
Convertible Debt | Convertible Senior Notes due 2023 | Debt Instrument, Redemption, Period Two
Debt Instrument [Line Items]
Threshold percentage of stock price trigger	98.00%
Threshold consecutive trading days | day	10
Reported Value Measurement | Convertible Senior Notes due 2023
Debt Instrument [Line Items]
Long-term debt, fair value	$ 272,200,000	$ 272,200,000

Stock-based Compensation - Addi

Stock-based Compensation - Additional Information (Details) - USD ($) $ in Thousands	Jan. 02, 2018	Mar. 31, 2018	Mar. 31, 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense—acquisitions		$ 714	$ 842
Stock options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total unrecognized compensation		$ 28,500
Total unrecognized compensation, period of recognition		3 years 3 months 19 days
RSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total unrecognized compensation, period of recognition		3 years 6 months 15 days
Total unrecognized compensation		$ 73,300
2015 Equity Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Maximum number of additional shares issued annually (in shares)	6,088,461
Number of shares authorized (in shares)		29,436,374
Number of shares available for grant (in shares)		18,316,257

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, 2018	Mar. 31, 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Volatility, minimum	41.90%	42.20%
Volatility, maximum	42.10%	42.70%
Risk-free interest rate, minimum	2.60%	2.10%
Risk-free interest rate, maximum	2.70%	2.20%
Expected term (in years)		6 years 3 months
Dividend rate	0.00%	0.00%
Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected term (in years)	5 years 11 months 23 days
Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected term (in years)	6 years 3 months

Stock-based Compensation - Summ

Stock-based Compensation - Summary of Stock Option Activity (Details) $ / shares in Units, $ in Thousands	3 Months Ended
	Mar. 31, 2018USD ($)$ / sharesshares
Shares
Outstanding, beginning balance (in shares) | shares	7,947,939
Granted (in shares) | shares	622,476
Exercised (in shares) | shares	(887,906)
Forfeited/Canceled (in shares) | shares	(108,541)
Outstanding, ending balance (in shares) | shares	7,573,968
Total exercisable at March 31, 2018 (in shares) | shares	1,551,029
Weighted-Average Exercise Price
Outstanding, beginning balance (in dollars per share) | $ / shares	$ 11.02
Granted (in dollars per share) | $ / shares	26.76
Exercised (in dollars per share) | $ / shares	11.54
Forfeited/Canceled (in dollars per share) | $ / shares	13.85
Outstanding, ending balance (in dollars per share) | $ / shares	12.27
Total exercisable at March 31, 2018 (in dollars per share) | $ / shares	$ 9.95
Weighted-Average Remaining Contract Term (in years)
Outstanding at March 31, 2018, Weighted-Average Remaining Contract Term	8 years 6 months
Total exercisable at March 31, 2018, Weighted-Average Remaining Contract Term	6 years 2 months 16 days
Aggregate Intrinsic Value
Outstanding at March 31, 2018, Aggregate Intrinsic Value | $	$ 119,764
Total exercisable at March 31, 2018, Aggregate Intrinsic Value | $	$ 28,082

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, 2018	Mar. 31, 2017
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Weighted average grant date fair value of options (in dollars per share)	$ 12.31	$ 4.66
Intrinsic value of options exercised	$ 9,799	$ 1,732
Fair value of awards vested	$ 2,930	$ 3,790

Stock-based Compensation - Su39

Stock-based Compensation - Summary of Unvested RSUs (Details) - RSUs	3 Months Ended
	Mar. 31, 2018$ / sharesshares
Shares
Unvested at December 31, 2017 (in shares) | shares	3,074,247
Granted (in shares) | shares	1,824,704
Vested (in shares) | shares	(191,925)
Forfeited/Cancelled (in shares) | shares	(123,980)
Unvested at March 31, 2018 (in shares) | shares	4,583,046
Weighted-Average Grant Date Fair Value
Unvested at December 31, 2017 (in dollars per share) | $ / shares	$ 11.98
Granted (in dollars per share) | $ / shares	27
Vested (in dollars per share) | $ / shares	11.04
Forfeited/Cancelled (in dollars per share) | $ / shares	12.15
Unvested at March 31, 2018 (in dollars per share) | $ / shares	$ 17.99

Stock-based Compensation - Allo

Stock-based Compensation - Allocated Share-Based Compensation Expense (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation expense	$ 6,454	$ 4,885
Cost of revenue
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation expense	546	364
Marketing
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation expense	478	444
Product development
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation expense	2,639	2,020
General and administrative
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation expense	$ 2,791	$ 2,057

Stockholders' Equity (Details)

Stockholders' Equity (Details) - USD ($)	3 Months Ended	12 Months Ended	15 Months Ended
	Mar. 31, 2018	Dec. 31, 2017	Mar. 31, 2018	Nov. 17, 2017
Equity [Abstract]
Stock repurchase program, authorized amount				$ 100,000,000
Shares repurchased (in shares)	2,807,393	586,231	3,393,624
Average price paid per share (in dollars per share)	$ 24.43	$ 17.57	$ 23.25
Stock repurchased and retired during period	$ 68,586,000	$ 10,301,000	$ 78,887,000
Stock repurchase program, remaining authorized repurchase amount	$ 21,113,000	$ 89,699,000	$ 21,113,000

Income Taxes (Details)

Income Taxes (Details) - Unrecognized Tax Benefit - USD ($) $ in Millions	Mar. 31, 2018	Dec. 31, 2017
Significant Change in Unrecognized Tax Benefits is Reasonably Possible [Line Items]
Unrecognized tax benefits		$ 17
Unrecognized tax benefits that would impact effective tax rate favorably	$ 17

Fair Value Measurements - Sched

Fair Value Measurements - Schedule of Major Categories of Assets and Liabilities Measured at Fair Value on a Recurring Basis (Details) - Recurring - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash equivalents	$ 451,028	$ 241,146
Short-term investments	67,526	25,108
Funds receivable and customer accounts	20,071	14,144
Asset	538,625	280,398
Commercial paper
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash equivalents	6,987	11,290
Short-term investments	32,952	2,998
Corporate bonds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Short-term investments	24,629	12,748
Money market funds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash equivalents	444,041	204,867
Funds receivable and customer accounts	20,071	14,144
U.S. Government and agency securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash equivalents		24,989
U.S. Government and agency securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Short-term investments	9,945	9,362
Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash equivalents	444,041	229,856
Short-term investments	9,945	9,362
Funds receivable and customer accounts	20,071	14,144
Asset	474,057	253,362
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
Level 1 | Corporate bonds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Short-term investments	0	0
Level 1 | Money market funds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash equivalents	444,041	204,867
Funds receivable and customer accounts	20,071	14,144
Level 1 | U.S. Government and agency securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash equivalents		24,989
Level 1 | U.S. Government and agency securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Short-term investments	9,945	9,362
Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash equivalents	6,987	11,290
Short-term investments	57,581	15,746
Funds receivable and customer accounts	0	0
Asset	64,568	27,036
Level 2 | Commercial paper
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash equivalents	6,987	11,290
Short-term investments	32,952	2,998
Level 2 | Corporate bonds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Short-term investments	24,629	12,748
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 customer accounts	0	0
Level 2 | U.S. Government and agency securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash equivalents		0
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
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 customer accounts	0	0
Asset	0	0
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
Level 3 | Corporate bonds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Short-term investments	0	0
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 customer accounts	0	0
Level 3 | U.S. Government and agency securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash equivalents		0
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

Fair Value Measurements - Sch44

Fair Value Measurements - Schedule of Long Term Debt Fair Value (Details) - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Long-term debt, net	$ 265,415	$ 0
Recurring | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Long-term debt, net	265,415	0
Long-term debt, fair value	$ 272,194	$ 0

Marketable Securities (Details)

Marketable Securities (Details) - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
Schedule of Available-for-sale Securities [Line Items]
Cost	$ 74,547	$ 61,384
Gross Unrealized Holding Loss	(34)	(8)
Gross Unrealized Holding Gain	0	11
Fair Value	74,513	61,387
Cash and Cash Equivalents
Schedule of Available-for-sale Securities [Line Items]
Cost	6,987	36,280
Gross Unrealized Holding Loss	0	(1)
Gross Unrealized Holding Gain	0	0
Fair Value	6,987	36,279
Cash and Cash Equivalents | Commercial paper
Schedule of Available-for-sale Securities [Line Items]
Cost	6,987	11,290
Gross Unrealized Holding Loss	0	0
Gross Unrealized Holding Gain	0	0
Fair Value	6,987	11,290
Cash and Cash Equivalents | U.S. Government and agency securities
Schedule of Available-for-sale Securities [Line Items]
Cost		24,990
Gross Unrealized Holding Loss		(1)
Gross Unrealized Holding Gain		0
Fair Value		24,989
Short-term Investments
Schedule of Available-for-sale Securities [Line Items]
Cost	67,560	25,104
Gross Unrealized Holding Loss	(34)	(7)
Gross Unrealized Holding Gain	0	11
Fair Value	67,526	25,108
Short-term Investments | Commercial paper
Schedule of Available-for-sale Securities [Line Items]
Cost	32,952	2,998
Gross Unrealized Holding Loss	0	0
Gross Unrealized Holding Gain	0	0
Fair Value	32,952	2,998
Short-term Investments | Corporate bonds
Schedule of Available-for-sale Securities [Line Items]
Cost	24,658	12,754
Gross Unrealized Holding Loss	(29)	(6)
Gross Unrealized Holding Gain	0	0
Fair Value	24,629	12,748
Short-term Investments | U.S. Government and agency securities
Schedule of Available-for-sale Securities [Line Items]
Cost	9,950	9,352
Gross Unrealized Holding Loss	(5)	(1)
Gross Unrealized Holding Gain	0	11
Fair Value	$ 9,945	$ 9,362

Net Income (Loss) Per Share - C

Net Income (Loss) Per Share - Calculation of Basic and Diluted Net Loss Per Share (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Numerator:
Net income (loss)	$ 12,967	$ (421)
Net income allocated to participating securities under the two-class method	(13)	0
Net income (loss) applicable to common stockholders—basic	12,954	(421)
Dilutive effect of net income allocated to participating securities under the two-class method	13	0
Net income (loss) attributable to common stockholders—diluted	$ 12,967	$ (421)
Denominator:
Weighted average common shares outstanding—basic (in shares)	121,267,092	115,696,024
Weighted average common shares outstanding - diluted (in shares)	125,772,315	115,696,024
Net (loss) income per share applicable to common stockholders—basic (in dollars per shares)	$ 0.11	$ 0
Net (loss) income per share applicable to common stockholders—diluted (in dollars per share)	$ 0.10	$ 0
Participating securities excluded from computation of earnings per share (in shares)	653,945	13,090,569
Participating Securities
Denominator:
Participating securities excluded from computation of earnings per share (in shares)	114,963
Stock Options
Denominator:
Dilutive effect of common equivalent shares from options and restricted stock (in shares)	2,836,429	0
Restricted stock units
Denominator:
Dilutive effect of common equivalent shares from options and restricted stock (in shares)	1,608,854	0
Restricted Stock
Denominator:
Dilutive effect of common equivalent shares from options and restricted stock (in shares)	59,940	0

Net Income (Loss) Per Share - S

Net Income (Loss) Per Share - Summary of Shares Excluded from the Calculation of Diluted Net Loss Per Share (Details) - shares	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Anti-dilutive securities excluded from computation of earnings per share (in shares)	653,945	13,090,569
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)	225,099	9,543,393
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)	428,846	3,547,176

Segment and Geographic Inform48

Segment and Geographic Information (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Revenue, Major Customer [Line Items]
Revenues	$ 120,912	$ 96,891
Income (loss) before income taxes	12,981	(1,473)
Net income (loss)	12,967	(421)
United States
Revenue, Major Customer [Line Items]
Revenues	84,923	71,523
Income (loss) before income taxes	(1,200)	(9,603)
Net income (loss)	(953)	(8,326)
International
Revenue, Major Customer [Line Items]
Revenues	35,989	25,368
Income (loss) before income taxes	14,181	8,130
Net income (loss)	$ 13,920	$ 7,905

Commitments and Contingencies (

Commitments and Contingencies (Details) - USD ($)	Mar. 31, 2018	Dec. 31, 2017
Non-Income Tax Obligations
Loss Contingencies [Line Items]
Non-income tax obligation reserve	$ 2,300,000	$ 400,000
Convertible Senior Notes due 2023
Loss Contingencies [Line Items]
Interest rate, stated percentage	0.00%
Convertible Debt | Convertible Senior Notes due 2023
Loss Contingencies [Line Items]
Aggregate principle amount	$ 345,000,000

Restructuring and Other Exit 50

Restructuring and Other Exit Costs (Details) $ in Thousands	3 Months Ended		12 Months Ended
	Mar. 31, 2018USD ($)	Mar. 31, 2017USD ($)	Dec. 31, 2017USD ($)position
Restructuring and Related Activities [Abstract]
Expected number of positions eliminated | position			245
Number of positions eliminated, inception to date			23.00%
Restructuring costs (income) | $	$ (151)	$ 0	$ 13,900

Restructuring and Other Exit 51

Restructuring and Other Exit Costs - Restructuring Charges Recorded to Date (Details) - USD ($) $ in Thousands	3 Months Ended		12 Months Ended
	Mar. 31, 2018	Mar. 31, 2017	Dec. 31, 2017
Restructuring Cost and Reserve [Line Items]
Restructuring costs (income)	$ (151)	$ 0	$ 13,900
Restructuring Reserve [Roll Forward]
Beginning balance	1,342
Total restructuring and other exit costs (income)	(151)
Costs charged against equity/assets	0
Cash payments	(793)
Ending balance	398		1,342
Severance Charge
Restructuring Reserve [Roll Forward]
Beginning balance	1,308
Total restructuring and other exit costs (income)	(156)
Costs charged against equity/assets	0
Cash payments	(793)
Ending balance	359		1,308
Stock-Based Compensation
Restructuring Reserve [Roll Forward]
Beginning balance	0
Total restructuring and other exit costs (income)	0
Costs charged against equity/assets	0
Cash payments	0
Ending balance	0		0
Other Exit Costs
Restructuring Reserve [Roll Forward]
Beginning balance	34
Total restructuring and other exit costs (income)	5
Costs charged against equity/assets	0
Cash payments	0
Ending balance	39		$ 34
Cost of revenue
Restructuring Cost and Reserve [Line Items]
Restructuring costs (income)	(7)	0
Marketing Expense
Restructuring Cost and Reserve [Line Items]
Restructuring costs (income)	(58)	0
Product development
Restructuring Cost and Reserve [Line Items]
Restructuring costs (income)	(79)	0
General and administrative
Restructuring Cost and Reserve [Line Items]
Restructuring costs (income)	$ (7)	$ 0