Earnings Per Share (Computation Of Basic And Diluted Earnings Per Share) (Detail) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Earnings Per Share [Abstract]
Net income (loss) attributable to Avis Budget Group, Inc. for basic and diluted EPS	$ 529	$ (170)
Basic weighted average shares outstanding (in shares)	53.1	69.9
Non-vested stock (in shares)	1.4	0.0
Diluted weighted average shares outstanding (in shares)	54.5	69.9
Earnings (loss) per share:
Basic (in usd per share)	$ 9.96	$ (2.43)
Diluted (in usd per share)	$ 9.71	$ (2.43)
Non-vested stock awards
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities (in shares)	0.1	1.1