CONDENSED CONSOLIDATED STATEMENT OF INCOME - USD ($) shares in Millions, $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Income Statement [Abstract]
Net revenues	$ 2,687	$ 2,640	$ 5,330	$ 5,220
Cost of net revenues	630	597	1,231	1,156
Gross profit	2,057	2,043	4,099	4,064
Operating expenses:
Sales and marketing	817	838	1,559	1,594
Product development	322	352	619	686
General and administrative	274	368	583	638
Provision for transaction losses	71	66	143	138
Amortization of acquired intangible assets	12	13	25	23
Total operating expenses	1,496	1,637	2,929	3,079
Income from operations	561	406	1,170	985
Interest and other, net	(51)	301	13	269
Income before income taxes	510	707	1,183	1,254
Income tax provision	(107)	(69)	(259)	(209)
Income from continuing operations	403	638	924	1,045
Income (loss) from discontinued operations, net of income taxes	(1)	4	(4)	4
Net income	$ 402	$ 642	$ 920	$ 1,049
Income per share - basic:
Continuing operations (in usd per share)	$ 0.47	$ 0.64	$ 1.05	$ 1.04
Discontinued operations (in usd per share)	0	0	0	0
Net income per share - basic (in usd per share)	0.47	0.64	1.05	1.04
Income per share - diluted:
Continuing operations (in usd per share)	0.46	0.64	1.04	1.03
Discontinued operations (in usd per share)	0	0	0	0
Net income per share - diluted (in usd per share)	$ 0.46	$ 0.64	$ 1.04	$ 1.03
Weighted-average shares:
Basic (in shares)	860	992	880	1,001
Diluted (in shares)	867	1,004	887	1,016