Financial Instruments (Narrative) (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2013		Mar. 31, 2012
Schedule of Cost-method Investments [Line Items]
Gain (Loss) on Derivative Used in Net Investment Hedge, Net of Tax	$ 3
Cash Flow Hedge Gain (Loss) to be Reclassified within Twelve Months	1
Cash posted as collateral for derivatives in a liability position	4
Derivative Instruments, Gain (Loss) Recognized in Income, Net	6		4
Interest Rate Caps [Member]
Schedule of Cost-method Investments [Line Items]
Absolute notional values of derivative instruments	6,992,000	[1]
Interest Rate Caps [Member] | Interest Rate Caps Purchased [Member]
Schedule of Cost-method Investments [Line Items]
Absolute notional values of derivative instruments	2,300
Interest Rate Caps [Member] | Interest Rate Caps Purchased [Member] | Subsidiary Issuers [Member]
Schedule of Cost-method Investments [Line Items]
Absolute notional values of derivative instruments	2,400
Interest Rate Caps [Member] | Interest Rate Caps Sold [Member]
Schedule of Cost-method Investments [Line Items]
Absolute notional values of derivative instruments	4,700
Interest Rate Swaps [Member]
Schedule of Cost-method Investments [Line Items]
Absolute notional values of derivative instruments	913
Foreign Exchange Contracts [Member]
Schedule of Cost-method Investments [Line Items]
Absolute notional values of derivative instruments	252
Commodity Contracts [Member]
Schedule of Cost-method Investments [Line Items]
Units Of Gasoline	9,000,000
Foreign Exchange Contract [Member]
Schedule of Cost-method Investments [Line Items]
Absolute notional values of derivative instruments	763
Not Designated As Hedging Instruments [Member] | Foreign Exchange Contracts [Member]
Schedule of Cost-method Investments [Line Items]
Derivative Instruments Gain Loss Recognized In Operations	2
Derivative Instruments, Gain (Loss) Recognized in Income, Net	1	[2]	(4)	[2]
Not Designated As Hedging Instruments [Member] | Commodity Contracts [Member]
Schedule of Cost-method Investments [Line Items]
Derivative Instruments, Gain (Loss) Recognized in Income, Net	$ 2	[3]	$ 6	[3]

[1] Represents $4.7 billion of interest rate caps sold, partially offset by approximately $2.3 billion of interest rate caps purchased, which amount excludes $2.4 billion of interest rate caps purchased by the Company’s Avis Budget Rental Car Funding (AESOP) LLC (“Avis Budget Rental Car Funding”) subsidiary.

[2] For the three months ended March 31, 2013, included a $2 million gain in operating expenses, and included a $1 million loss in interest expense. For the three months ended March 31, 2012, amounts were included in operating expenses.

[3] Included in operating expense.