Condensed Consolidated Statements of Cash Flows - USD ($) $ in Millions	6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020
Operating activities:
Net income (loss)	$ (120)	$ (169)
Adjustments to reconcile net income (loss) to net cash provided by (used in) operating activities:
Depreciation and amortization	57	64
Stock-based compensation expense (Note 9)	61	51
Deferred income tax expense (benefit)	(29)	6
Provision for expected credit losses	3	15
Other, net	8	9
Changes in operating assets and liabilities, net of effects from acquisitions and other investments:
Accounts receivable and contract assets, prepaid expenses and other assets	(87)	95
Accounts payable, accrued expenses and other liabilities	48	(46)
Deferred merchant payables	138	(100)
Income tax receivables/payables, net	6	(50)
Deferred revenue	21	(23)
Net cash provided by (used in) operating activities	106	(148)
Investing activities:
Capital expenditures, including internal-use software and website development	(25)	(36)
Other investing activities, net	(1)	2
Net cash provided by (used in) investing activities	(26)	(34)
Financing activities:
Repurchase of common stock (Note 10)		(115)
Proceeds from issuance of 2026 Senior Notes, net of financing costs (Note 6)	340
Purchase of capped calls in connection with 2026 Senior Notes (Note 6)	(35)
Proceeds from exercise of stock options	8
Payment of withholding taxes on net share settlements of equity awards	(29)	(17)
Payments of finance lease obligation	(3)	(3)
Net cash provided by (used in) financing activities	281	561
Effect of exchange rate changes on cash, cash equivalents and restricted cash	(4)
Net increase in cash, cash equivalents and restricted cash	357	379
Cash, cash equivalents and restricted cash at beginning of period	418	319
Cash, cash equivalents and restricted cash at end of period	$ 775	698
2015 Credit Facility
Financing activities:
Proceeds from 2015 credit facility (Note 6)		700
Payment of financing costs related to 2015 credit facility		$ (4)