Reconciliation of Adjusted EBITDA to Income (Loss) (Detail) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2013		Dec. 31, 2012		Dec. 31, 2011
Segment Reporting [Abstract]
Adjusted EBITDA	$ 708	[1]	$ 802	[1]	$ 605	[1]
Non-vehicle depreciation and amortization	152		125		95
Interest expense related to corporate debt, net	228		268		219
Early extinguishment of debt	147		75		0
Transaction-related costs	51		34		255
Transaction-related costs	33		0		0
Income before income taxes	$ 97		$ 300		$ 36

[1] Adjusted EBITDA includes restructuring costs of $61 million, $38 million and $5 million for the years ended December 31, 2013, 2012 and 2011, respectively.