Hedging Activities (Summary Of Notional Amounts And Respective Fair Values Of Derivative Financial Instruments) (Details) (USD $) In Millions, unless otherwise specified	Jun. 30, 2012	Dec. 31, 2011
Derivatives Fair Value [Line Items]
Total derivatives - Notional amount	$ 3,079	$ 3,996
Asset derivatives, Fair value	49	12
Liability derivatives, Fair value	(38)	(169)
Foreign Exchange Contracts [Member]
Derivatives Fair Value [Line Items]
Derivatives designated as hedging instruments - Notional amount	484	402
Derivatives not designated as hedging instruments - Notional amount	2,595	3,094
Benchmark Interest Rate [Member]
Derivatives Fair Value [Line Items]
Derivatives designated as hedging instruments - Notional amount		500
Other Current Assets [Member]
Derivatives Fair Value [Line Items]
Derivative not designated as hedging instruments - Fair value	30	6
Designated As Hedging Instruments [Member] | Other Current Assets [Member]
Derivatives Fair Value [Line Items]
Asset derivatives, Fair value	17	6
Designated As Hedging Instruments [Member] | Other Accrued Liabilities [Member]
Derivatives Fair Value [Line Items]
Liability derivatives, Fair value	(2)	(8)
Designated As Hedging Instruments [Member] | Other Liabilities [Member]
Derivatives Fair Value [Line Items]
Liability derivatives, Fair value		(33)
Designated As Hedging Instruments [Member] | Other Assets [Member]
Derivatives Fair Value [Line Items]
Asset derivatives, Fair value	2
Not Designated As Hedging Instruments [Member] | Other Accrued Liabilities [Member]
Derivatives Fair Value [Line Items]
Liability derivatives, Fair value	(32)	(122)
Not Designated As Hedging Instruments [Member] | Other Liabilities [Member]
Derivatives Fair Value [Line Items]
Liability derivatives, Fair value	$ (4)	$ (6)