Financial Instruments, Summary of Derivative Instruments Fair Value (Details) (USD $) In Millions, unless otherwise specified	Sep. 30, 2012	Dec. 31, 2011
Summary Of Derivative Instruments By Hedge Designation [Abstract]
Total Derivative Assets	$ 28	$ 58
Total Derivative Liabilities	(11)	(31)
Net Derivative Asset	17	27
Derivatives Designated as Hedging Instruments [Member]
Summary Of Derivative Instruments By Hedge Designation [Abstract]
Net Derivative Asset	19	26
Derivatives Designated as Hedging Instruments [Member] | Foreign exchange contracts - forwards [Member] | Other current assets [Member]
Summary Of Derivative Instruments By Hedge Designation [Abstract]
Total Derivative Assets	21	37
Derivatives Designated as Hedging Instruments [Member] | Foreign exchange contracts - forwards [Member] | Other current liabilities [Member]
Summary Of Derivative Instruments By Hedge Designation [Abstract]
Total Derivative Liabilities	(2)	(11)
Not Designated as Hedging Instrument [Member]
Summary Of Derivative Instruments By Hedge Designation [Abstract]
Net Derivative Asset	(2)	1
Not Designated as Hedging Instrument [Member] | Foreign exchange contracts - forwards [Member] | Other current assets [Member]
Summary Of Derivative Instruments By Hedge Designation [Abstract]
Total Derivative Assets	7	21
Not Designated as Hedging Instrument [Member] | Foreign exchange contracts - forwards [Member] | Other current liabilities [Member]
Summary Of Derivative Instruments By Hedge Designation [Abstract]
Total Derivative Liabilities	$ (9)	$ (20)