Earnings Per Share - Computation of Basic and Diluted Earnings Per Share (Detail) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Earnings Per Share [Abstract]
Net income attributable to Avis Budget Group, Inc.	$ 1,632	$ 2,764	$ 1,285
Basic weighted average shares outstanding (in shares)	38.3	47.3	64.9
Non-vested stock (in shares)	0.5	1.1	1.2
Diluted weighted average shares outstanding (in shares)	38.8	48.4	66.1
Earnings per share:
Basic (in USD per share)	$ 42.57	$ 58.41	$ 19.79
Diluted (in USD per share)	$ 42.08	$ 57.16	$ 19.44