Derivative Instruments and Hedging Activities (Details) (USD $) In Millions, unless otherwise specified	Mar. 31, 2012	Dec. 31, 2011
Derivative assets
Derivative assets	$ 69	$ 32
Derivative Liabilities
Derivative Liabilities	83	189
Designated as Hedging Instrument [Member]
Derivative assets
Derivative assets	56	15
Derivative Liabilities
Derivative Liabilities	78	177
Designated as Hedging Instrument [Member] | Other Assets [Member]
Derivative assets
Derivative assets	39
Nondesignated [Member]
Derivative assets
Derivative assets	13	17
Derivative Liabilities
Derivative Liabilities	5	12
Foreign Exchange Contracts [Member] | Designated as Hedging Instrument [Member] | Other Current Assets [Member]
Derivative assets
Derivative assets	9	2
Foreign Exchange Contracts [Member] | Designated as Hedging Instrument [Member] | Other Assets [Member]
Derivative assets
Derivative assets		4
Foreign Exchange Contracts [Member] | Designated as Hedging Instrument [Member] | Accounts Payable and Accrued Liabilities [Member]
Derivative Liabilities
Derivative Liabilities	13	47
Foreign Exchange Contracts [Member] | Designated as Hedging Instrument [Member] | Other Liabilities [Member]
Derivative Liabilities
Derivative Liabilities	65	130
Foreign Exchange Contracts [Member] | Nondesignated [Member] | Other Current Assets [Member]
Derivative assets
Derivative assets	6	8
Foreign Exchange Contracts [Member] | Nondesignated [Member] | Other Assets [Member]
Derivative assets
Derivative assets	7	9
Foreign Exchange Contracts [Member] | Nondesignated [Member] | Accounts Payable and Accrued Liabilities [Member]
Derivative Liabilities
Derivative Liabilities	5	9
Interest Rate Swaps [Member] | Designated as Hedging Instrument [Member] | Other Assets [Member]
Derivative assets
Derivative assets	8	9
Commodity Contracts [Member] | Nondesignated [Member] | Accounts Payable and Accrued Liabilities [Member]
Derivative Liabilities
Derivative Liabilities		$ 3