Financial Instruments (Details 1) (USD $) In Millions	Sep. 30, 2011	Dec. 31, 2010
Fair value of derivatives segregated between those derivatives that are designated as hedging instruments and those that are not designated as hedging instruments
Fair Value of Derivative, Asset	$ 864	$ 628
Fair Value of Derivative, Liability	144	61
Derivative Instruments Not Designated as Hedging Instruments [Abstract]
U.S. Dollar Notional, Foreign exchange contracts	22,209	20,446
Foreign exchange contract [Member] | Derivatives Designated as Hedging Instruments [Member] | Deferred income taxes and other current assets [Member]
Fair value of derivatives segregated between those derivatives that are designated as hedging instruments and those that are not designated as hedging instruments
Fair Value of Derivative, Asset	147	167
Fair Value of Derivative, Liability	0	0
Derivative Instruments Not Designated as Hedging Instruments [Abstract]
U.S. Dollar Notional, Foreign exchange contracts	3,115	2,344
Foreign exchange contract [Member] | Derivatives Designated as Hedging Instruments [Member] | Other Assets [Member]
Fair value of derivatives segregated between those derivatives that are designated as hedging instruments and those that are not designated as hedging instruments
Fair Value of Derivative, Asset	364	310
Fair Value of Derivative, Liability	0	0
Derivative Instruments Not Designated as Hedging Instruments [Abstract]
U.S. Dollar Notional, Foreign exchange contracts	4,723	3,720
Foreign exchange contract [Member] | Derivatives Designated as Hedging Instruments [Member] | Deferred Income Taxes And Noncurrent Liabilities [Member]
Fair value of derivatives segregated between those derivatives that are designated as hedging instruments and those that are not designated as hedging instruments
Fair Value of Derivative, Asset	0	0
Fair Value of Derivative, Liability	2	6
Derivative Instruments Not Designated as Hedging Instruments [Abstract]
U.S. Dollar Notional, Foreign exchange contracts	59	503
Foreign exchange contract [Member] | Derivatives Designated as Hedging Instruments [Member] | Accrued and other current liabilities [Member]
Fair value of derivatives segregated between those derivatives that are designated as hedging instruments and those that are not designated as hedging instruments
Fair Value of Derivative, Asset	0	0
Fair Value of Derivative, Liability	121	18
Derivative Instruments Not Designated as Hedging Instruments [Abstract]
U.S. Dollar Notional, Foreign exchange contracts	2,390	1,505
Foreign exchange contract [Member] | Derivatives Not Designated as Hedging Instruments [Member] | Deferred income taxes and other current assets [Member]
Fair value of derivatives segregated between those derivatives that are designated as hedging instruments and those that are not designated as hedging instruments
Fair Value of Derivative, Asset	347	95
Fair Value of Derivative, Liability	0	0
Derivative Instruments Not Designated as Hedging Instruments [Abstract]
U.S. Dollar Notional, Foreign exchange contracts	9,496	6,295
Foreign exchange contract [Member] | Derivatives Not Designated as Hedging Instruments [Member] | Accrued and other current liabilities [Member]
Fair value of derivatives segregated between those derivatives that are designated as hedging instruments and those that are not designated as hedging instruments
Fair Value of Derivative, Asset	0	0
Fair Value of Derivative, Liability	21	30
Derivative Instruments Not Designated as Hedging Instruments [Abstract]
U.S. Dollar Notional, Foreign exchange contracts	2,176	4,229
Interest rate swap contract [Member] | Derivatives Designated as Hedging Instruments [Member] | Deferred income taxes and other current assets [Member]
Fair value of derivatives segregated between those derivatives that are designated as hedging instruments and those that are not designated as hedging instruments
Fair Value of Derivative, Asset	6	0
Fair Value of Derivative, Liability	0	0
Derivative Instruments Not Designated as Hedging Instruments [Abstract]
U.S. Dollar Notional, Foreign exchange contracts	250	0
Interest rate swap contract [Member] | Derivatives Designated as Hedging Instruments [Member] | Other Assets [Member]
Fair value of derivatives segregated between those derivatives that are designated as hedging instruments and those that are not designated as hedging instruments
Fair Value of Derivative, Asset	0	56
Fair Value of Derivative, Liability	0	0
Derivative Instruments Not Designated as Hedging Instruments [Abstract]
U.S. Dollar Notional, Foreign exchange contracts	0	1,000
Interest rate swap contract [Member] | Derivatives Designated as Hedging Instruments [Member] | Deferred Income Taxes And Noncurrent Liabilities [Member]
Fair value of derivatives segregated between those derivatives that are designated as hedging instruments and those that are not designated as hedging instruments
Fair Value of Derivative, Asset	0	0
Fair Value of Derivative, Liability	0	7
Derivative Instruments Not Designated as Hedging Instruments [Abstract]
U.S. Dollar Notional, Foreign exchange contracts	0	850
Derivatives Designated as Hedging Instruments [Member]
Fair value of derivatives segregated between those derivatives that are designated as hedging instruments and those that are not designated as hedging instruments
Fair Value of Derivative, Asset	517	533
Fair Value of Derivative, Liability	123	31
Derivative Instruments Not Designated as Hedging Instruments [Abstract]
U.S. Dollar Notional, Foreign exchange contracts	10,537	9,922
Derivatives Not Designated as Hedging Instruments [Member]
Fair value of derivatives segregated between those derivatives that are designated as hedging instruments and those that are not designated as hedging instruments
Fair Value of Derivative, Asset	347	95
Fair Value of Derivative, Liability	21	30
Derivative Instruments Not Designated as Hedging Instruments [Abstract]
U.S. Dollar Notional, Foreign exchange contracts	$ 11,672	$ 10,524