Earnings Per Share - Basic and Diluted earnings per Share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Millions	3 Months Ended								12 Months Ended
	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Earnings Per Share [Abstract]
Net income attributable to Expedia Group, Inc.	$ 17	$ 525	$ 1	$ (137)	$ 55	$ 352	$ 57	$ (86)	$ 406	$ 378	$ 282
Basic (in dollars per share)	$ 0.11	$ 3.51	$ 0.01	$ (0.91)	$ 0.36	$ 2.32	$ 0.37	$ (0.57)	$ 2.71	$ 2.49	$ 1.87
Diluted (in dollars per share)	$ 0.11	$ 3.43	$ 0.01	$ (0.91)	$ 0.35	$ 2.23	$ 0.36	$ (0.57)	$ 2.65	$ 2.42	$ 1.82
Weighted average number of shares outstanding (000's):
Basic (in shares)									149,961	151,619	150,367
Dilutive effect of:
Options to purchase common stock									2,317	4,218	3,874
Other dilutive securities									611	548	276
Diluted (in shares)									152,889	156,385	154,517