Components of Company's Vehicles (Detail) - USD ($) $ in Millions	Dec. 31, 2015	Dec. 31, 2014
Disclosure Components Of Companys Vehicles [Abstract]
Rental vehicles	$ 11,195	$ 11,006
Less: Accumulated depreciation	(1,500)	(1,465)
Rental Vehicles Net, Total	9,695	9,541
Vehicles held for sale	963	674
Vehicles, net	$ 10,658	$ 10,215