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, 2025	Dec. 31, 2024	Dec. 31, 2023
Earnings Per Share [Abstract]
Net income (loss) attributable to Avis Budget Group, Inc. for basic and diluted EPS	$ (889)	$ (1,821)	$ 1,632
Basic weighted average shares outstanding (in shares)	35.2	35.5	38.3
Non-vested stock (in shares)	0.0	0.0	0.5
Diluted weighted average shares outstanding (in shares)	35.2	35.5	38.8
Earnings (loss) per share
Basic (in USD per share)	$ (25.25)	$ (51.23)	$ 42.57
Diluted (in USD per share)	$ (25.25)	$ (51.23)	$ 42.08