Basis Of Presentation And Recently Issued Accounting Pronouncements (Narrative) (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Basis Of Presentation And Recently Issued Accounting Pronouncements [Abstract]
Net unrealized gain or loss on foreign-currency transactions of intercompany loan hedges	$ (4)	$ (2)

Net unrealized gain or loss on foreign-currency transactions of intercompany loan hedges.

No definition available.

Name:	car_NetUnrealizedGainOrLossOfForeignCurrencyTransactionsOnIntercompanyLoanHedges
Namespace Prefix:	car_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration