Pretax Income (Loss) for Domestic and Foreign Operations (Parenthetical) (Detail) (USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Income Taxes [Line Items]
Transaction-related costs	$ 34	$ 255	$ 14
Foreign Tax Authority
Income Taxes [Line Items]
Transaction-related costs		$ 128

Costs incurred and charged to expense, associated with acquisition of businesses.

No definition available.

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