Income Taxes - Summary of Deferred Tax Assets and Deferred Tax Liabilities (Details) - USD ($) $ in Millions	Dec. 31, 2016	Dec. 31, 2015
Deferred tax assets:
Stock-based compensation	$ 52	$ 40
Net operating loss carryforwards	46	31
Provision for accrued expenses	12	12
Deferred rent	5	5
Lease financing obligation	33	33
Foreign advertising spend	10	8
Deferred expense related to cost-sharing arrangement	30	20
Charitable contribution carryforward	20	24
Other	7	4
Total deferred tax assets	215	177
Less: valuation allowance	(27)	(17)
Net deferred tax assets	188	160
Deferred tax liabilities:
Intangible assets	(83)	(81)
Property and equipment	(28)	(27)
Prepaid expenses	(6)	(4)
Building – corporate headquarters	(31)	(31)
Deferred income related to cost-sharing arrangement	(10)	(7)
Total deferred tax liabilities	(158)	(150)
Net deferred tax asset (liability)	$ 30	$ 10