Financial Instruments, Summary of Derivative Instruments Fair Value (Details) (USD $) In Millions, unless otherwise specified	Mar. 31, 2012	Dec. 31, 2011
Summary Of Derivative Instruments By Hedge Designation [Abstract]
Total Derivative Assets	$ 15	$ 58
Total Derivative Liabilities	(70)	(31)
Net Derivative (Liability) Asset	(55)	27
Derivatives Designated as Hedging Instruments [Member]
Summary Of Derivative Instruments By Hedge Designation [Abstract]
Total Derivative Assets		26
Total Derivative Liabilities	(27)
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	10	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	(37)	(11)
Not Designated as Hedging Instrument [Member]
Summary Of Derivative Instruments By Hedge Designation [Abstract]
Total Derivative Assets		1
Total Derivative Liabilities	(28)
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	5	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	$ (33)	$ (20)