Financial Instruments Hedging Activity Reported In Accumulated Other Comprehensive Earnings (Losses) Net Of Income Taxes (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2012	Mar. 31, 2011
Derivative [Line Items]
Gain (loss) at beginning of period	$ 15
Derivative Instruments, Gain (Loss) Reclassified from Accumulated OCI into Income, Effective Portion, Net	(10)	7
Derivative Instruments, Gain (Loss) Recognized in Other Comprehensive Income (Loss), Effective Portion, Net	46	22
Gain (loss) at end of period	51	31
Foreign Exchange Contract [Member]
Derivative [Line Items]
Gain (loss) at beginning of period	15	2
Derivative Instruments, Gain (Loss) Reclassified from Accumulated OCI into Income, Effective Portion, Net	(10)	7
Derivative Instruments, Gain (Loss) Recognized in Other Comprehensive Income (Loss), Effective Portion, Net	46	22
Gain (loss) at end of period	51	31
Derivative Instruments, gains to be reclassified to earnings.	$ 47