CONDENSED CONSOLIDATED STATEMENT OF INCOME - USD ($) shares in Millions, $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Income Statement [Abstract]
Net revenues	$ 2,328	$ 2,230	$ 4,545	$ 4,367
Cost of net revenues	561	493	1,076	970
Gross profit	1,767	1,737	3,469	3,397
Operating expenses:
Sales and marketing	637	622	1,199	1,160
Product development	313	295	591	534
General and administrative	267	218	512	427
Provision for transaction losses	63	64	125	116
Amortization of acquired intangible assets	9	7	18	15
Total operating expenses	1,289	1,206	2,445	2,252
Income from operations	478	531	1,024	1,145
Interest and other, net	(18)	(8)	(6)	(31)
Income before income taxes	460	523	1,018	1,114
Income tax benefit (provision)	(433)	(86)	44	(195)
Income from continuing operations	27	437	1,062	919
Loss from discontinued operations, net of income taxes	0	(2)	0	(2)
Net income	$ 27	$ 435	$ 1,062	$ 917
Income (loss) per share - basic:
Continuing operations (in usd per share)	$ 0.03	$ 0.38	$ 0.98	$ 0.80
Discontinued operations (in usd per share)	0.00	0.00	0.00	0.00
Net income per share - basic (in usd per share)	0.03	0.38	0.98	0.80
Income (loss) per share - diluted:
Continuing operations (in usd per share)	0.02	0.38	0.97	0.79
Discontinued operations (in usd per share)	0.00	0.00	0.00	0.00
Net income per share - diluted (in usd per share)	$ 0.02	$ 0.38	$ 0.97	$ 0.79
Weighted-average shares:
Basic (in shares)	1,076	1,144	1,080	1,151
Diluted (in shares)	1,091	1,149	1,097	1,159