Vehicle Rental Activities (Components Of The Company's Vehicles) (Detail) (USD $) In Millions, unless otherwise specified	Sep. 30, 2012	Dec. 31, 2011
Geographic Valuation Methodologies Of Inventory [Line Items]
Rental vehicles	$ 10,799	$ 9,077
Less: Accumulated depreciation	(1,323)	(1,258)
Rental Vehicles Net, Total	9,476	7,819
Vehicles held for sale	867	537
Vehicles, net	$ 10,343	$ 8,356