Valuation And Qualifying Accounts (Detail) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2013		Dec. 31, 2012		Dec. 31, 2011
Allowance for Doubtful Accounts
Valuation and Qualifying Accounts Disclosure [Line Items]
Balance at Beginning of Period	$ 40		$ 21		$ 16
Expensed	15		27		9
Other Adjustments	10		0		0
Deductions	(15)		(8)		(4)
Balance at End of Period	50		40		21
Tax Valuation Allowance
Valuation and Qualifying Accounts Disclosure [Line Items]
Balance at Beginning of Period	298	[1]	273	[1]	192	[1]
Expensed	27	[1]	25		16	[1]
Other Adjustments	22	[1]	0		65	[1]
Deductions	0	[1]	0		0	[1]
Balance at End of Period	$ 347	[1]	$ 298	[1]	$ 273	[1]

[1] For 2013 and 2011, other adjustments relate to the acquisition of Zipcar and Avis Europe, respectively.