Financial Instruments (Details 2) (USD $) In Millions, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2012	Sep. 30, 2011
Schedule of impact that changes in fair values of derivatives
Derivative Instruments, Gain (Loss) Recognized in Income, Net	$ 1	$ (64)	$ (11)	$ 1
Derivatives designated as hedging instruments: [Member] | Interest rate swaps [Member] | Interest expense, net [Member]
Schedule of impact that changes in fair values of derivatives
Derivative Instruments, Gain (Loss) Recognized in Income, Net		(2)		(7)
Derivatives not designated as hedging instruments: [Member] | Interest rate swaps [Member] | Interest expense, net [Member]
Schedule of impact that changes in fair values of derivatives
Derivative Instruments, Gain (Loss) Recognized in Income, Net	(2)	2	(3)	(9)
Derivatives not designated as hedging instruments: [Member] | Foreign currency 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	3	(63)	(8)	3
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		$ (1)		$ 14