Condensed Consolidated Statements of Cash Flows - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Operating activities:
Net income	$ 5	$ 13
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation of property and equipment, including amortization of internal-use software and website development	20	19
Amortization of intangible assets	8	8
Stock-based compensation expense	29	19
Other, net		6
Changes in operating assets and liabilities, net of effects from acquisitions:
Accounts receivable, prepaid expenses and other assets	(55)	(35)
Accounts payable, accrued expenses and other liabilities		(8)
Deferred merchant payables	110	88
Income tax receivables/payables, net	15
Deferred revenue	42	24
Net cash provided by operating activities	174	134
Investing activities:
Capital expenditures, including internal-use software and website development	(15)	(18)
Purchases of marketable securities	(1)
Sales of marketable securities	41	102
Maturities of marketable securities	3	14
Net cash provided by investing activities	28	98
Financing activities:
Repurchase of common stock	(4)	(150)
Proceeds from exercise of stock options		3
Payment of withholding taxes on net share settlements of equity awards	(12)	(13)
Net cash used in financing activities	(246)	(114)
Effect of exchange rate changes on cash, cash equivalents and restricted cash	6	1
Net (decrease) increase in cash, cash equivalents and restricted cash	(38)	119
Cash, cash equivalents and restricted cash at beginning of period	673	612
Cash, cash equivalents and restricted cash at end of period	635	731
Supplemental disclosure of non-cash investing and financing activities:
Stock-based compensation capitalized with internal-use software and website development costs	3	3
2015 Credit Facility
Financing activities:
Proceeds from credit facility	5	270
Payments to credit facility	$ (235)	(151)
2016 Credit Facility
Financing activities:
Payments to credit facility		$ (73)