Financial Instruments (Details 2) (USD $) In Millions, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2012	Jun. 30, 2011	Jun. 30, 2012	Jun. 30, 2011
Derivatives designated as hedging instruments: [Member] | Interest rate swaps [Member]
Schedule of impact that changes in fair values of derivatives
Derivative Instruments, Gain (Loss) Recognized in Income, Net		$ (3)		$ (5)
Derivatives not designated as hedging instruments: [Member]
Schedule of impact that changes in fair values of derivatives
Derivative Instruments, Gain (Loss) Recognized in Income, Net	(27)	19	(12)	65
Derivatives not designated as hedging instruments: [Member] | Interest rate swaps [Member]
Schedule of impact that changes in fair values of derivatives
Derivative Instruments, Gain (Loss) Recognized in Income, Net	(2)	(3)	(1)	(11)
Derivatives not designated as hedging instruments: [Member] | Foreign exchange impact of cross currency swaps [Member] | Selling, general and administrative [Member]
Schedule of impact that changes in fair values of derivatives
Derivative Instruments, Gain (Loss) Recognized in Income, Net	(25)	21	(11)	66
Derivatives not designated as hedging instruments: [Member] | Foreign exchange forward contracts [Member] | Selling, general and administrative [Member]
Schedule of impact that changes in fair values of derivatives
Derivative Instruments, Gain (Loss) Recognized in Income, Net		$ 4		$ 15