Segment Information - Reconciliation of Segment Adjusted OBIDA to Earnings (Loss) Before Income Taxes (Details) - USD ($)	3 Months Ended								12 Months Ended
	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Segment Information
Combined segment Adjusted OIBDA									$ 1,638,000,000	$ 146,000,000	$ 33,000,000
Legal reserves, occupancy tax and other									(25,000,000)	2,000,000
Restructuring and related reorganization charges									(17,000,000)	(9,000,000)
Stock-based compensation									(126,000,000)	(47,000,000)	(2,000,000)
Depreciation and amortization									(2,266,000,000)	(481,000,000)	(21,000,000)
Goodwill and Intangible Asset Impairment									(2,197,000,000)
Operating income (loss)	$ (2,434,000,000)	$ 152,000,000	$ (242,000,000)	$ (469,000,000)	$ (397,000,000)	$ 2,000,000	$ 3,000,000	$ 3,000,000	(2,993,000,000)	(389,000,000)	10,000,000
Interest expense									(125,000,000)	(19,000,000)	(1,000,000)
Share of earnings (losses) of Expedia										26,000,000	117,000,000
Gain (loss) on dilution of Expedia									0	(2,000,000)	320,000,000
Gain on consolidation of Expedia										2,005,000,000
Other, net									(28,000,000)		(1,000,000)
Earnings (loss) before income taxes									$ (3,146,000,000)	$ 1,621,000,000	$ 445,000,000