Financial Instruments (Narrative) (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2014		Mar. 31, 2013
Schedule of Cost-method Investments [Line Items]
Interest Rate Cash Flow Hedge Gain (Loss) to be Reclassified During Next 12 Months, Net	$ 6
Cash posted as collateral for derivatives in a liability position	1
Derivative Instruments, Gain (Loss) Recognized in Income, Net	(17)	[1]	6	[1]
Interest Rate Caps [Member]
Schedule of Cost-method Investments [Line Items]
Absolute notional values of derivative instruments	11,981	[2]
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	7,500
Interest Rate Caps [Member] | Interest Rate Caps Sold [Member]
Schedule of Cost-method Investments [Line Items]
Absolute notional values of derivative instruments	9,700
Interest Rate Swaps [Member]
Schedule of Cost-method Investments [Line Items]
Absolute notional values of derivative instruments	1,503
Commodity Contracts [Member]
Schedule of Cost-method Investments [Line Items]
Units Of Gasoline	7,000,000
Currency Swap [Member]
Schedule of Cost-method Investments [Line Items]
Absolute notional values of derivative instruments	548
Not Designated As Hedging Instruments [Member] | Commodity Contracts [Member]
Schedule of Cost-method Investments [Line Items]
Derivative Instruments, Gain (Loss) Recognized in Income, Net	0	[3]	2	[3]
Operating Expense [Member]
Schedule of Cost-method Investments [Line Items]
Derivative Instruments, Gain (Loss) Recognized in Income, Net	$ 4		$ 2

[1] Gains (losses) related to derivative instruments are expected to be largely offset by (losses) gains on the underlying exposures being hedged.

[2] Represents $9.7 billion of interest rate caps sold, partially offset by approximately $2.3 billion of interest rate caps purchased. These amounts exclude $7.5 billion of interest rate caps purchased by the Company’s Avis Budget Rental Car Funding subsidiary.

[3] Included in operating expenses.