Basis Of Presentation And Recently Issued Accounting Pronouncements (Narrative) (Detail) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Basis Of Presentation And Recently Issued Accounting Pronouncements [Abstract]
Net unrealized gain or loss on foreign-currency transactions of intercompany loan hedges	$ (1)	$ (1)	$ (8)	$ (10)

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