CONDENSED CONSOLIDATED STATEMENT OF INCOME - USD ($) shares in Millions, $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Income Statement [Abstract]
Net revenues	$ 2,640	$ 2,419	$ 5,220	$ 4,722
Cost of net revenues	597	560	1,156	1,074
Gross profit	2,043	1,859	4,064	3,648
Operating expenses:
Sales and marketing	838	727	1,594	1,375
Product development	352	313	686	591
General and administrative	368	267	638	512
Provision for transaction losses	66	63	138	125
Amortization of acquired intangible assets	13	9	23	18
Total operating expenses	1,637	1,379	3,079	2,621
Income from operations	406	480	985	1,027
Interest and other, net	301	(18)	269	(7)
Income before income taxes	707	462	1,254	1,020
Income tax benefit (provision)	(69)	(433)	(209)	44
Income from continuing operations	638	29	1,045	1,064
Income from discontinued operations, net of income taxes	4	0	4	0
Net income	$ 642	$ 29	$ 1,049	$ 1,064
Income per share - basic:
Continuing operations (in usd per share)	$ 0.64	$ 0.03	$ 1.04	$ 0.99
Discontinued operations (in usd per share)	0	0	0	0
Net income per share - basic (in usd per share)	0.64	0.03	1.04	0.99
Income per share - diluted:
Continuing operations (in usd per share)	0.64	0.03	1.03	0.97
Discontinued operations (in usd per share)	0	0	0	0
Net income per share - diluted (in usd per share)	$ 0.64	$ 0.03	$ 1.03	$ 0.97
Weighted-average shares:
Basic (in shares)	992	1,076	1,001	1,080
Diluted (in shares)	1,004	1,091	1,016	1,097