Segment Information - Performance Measures (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Segment Reporting, Revenue Reconciling Item [Line Items]
Revenue from external customers	$ 2,574	$ 2,230
Adjusted OIBDA	123	160
Operating Segments
Segment Reporting, Revenue Reconciling Item [Line Items]
Revenue from external customers	2,574	2,230
Adjusted OIBDA	123	160
Expedia
Segment Reporting, Revenue Reconciling Item [Line Items]
Revenue from external customers	2,508	2,139
Adjusted OIBDA	127	155
Corporate and Other
Segment Reporting, Revenue Reconciling Item [Line Items]
Revenue from external customers	66	91
Adjusted OIBDA	$ (4)	$ 5