Derivative Instruments Derivative Instruments and Hedging Activities, Fair Value of Outstanding Derivatives (Details) (USD $) In Millions, unless otherwise specified	Sep. 30, 2013	Dec. 31, 2012
Foreign Exchange Contract [Member]
Fair Value of Derivative Contracts:
Derivative Asset, Fair Value, Amount Offset Against Collateral	$ 46
Derivative Liability, Fair Value, Amount Offset Against Collateral	46
Other Current Assets [Member]
Fair Value of Derivative Contracts:
Derivative Asset, Fair Value, Gross Asset	46	55
Other Current Assets [Member] | Foreign Exchange Contract [Member]
Fair Value of Derivative Contracts:
Derivative assets	93
Other Current Assets [Member] | Not Designated as Hedging Instrument [Member] | Foreign Exchange Contract [Member]
Fair Value of Derivative Contracts:
Derivative Asset, Fair Value, Gross Asset	30	43
Other Current Assets [Member] | Not Designated as Hedging Instrument [Member] | Embedded Derivative Financial Instruments [Member]
Fair Value of Derivative Contracts:
Derivative Asset, Fair Value, Gross Asset	0	11
Other Current Assets [Member] | Cash Flow Hedging [Member] | Designated as Hedging Instrument [Member] | Foreign Exchange Contract [Member]
Fair Value of Derivative Contracts:
Derivative Asset, Fair Value, Gross Asset	16	1
Other Current Liabilities [Member]
Fair Value of Derivative Contracts:
Derivative Liability, Fair Value, Gross Liability	139	86
Other Current Liabilities [Member] | Not Designated as Hedging Instrument [Member] | Foreign Exchange Contract [Member]
Fair Value of Derivative Contracts:
Derivative Liability, Fair Value, Gross Liability	44	30
Other Current Liabilities [Member] | Not Designated as Hedging Instrument [Member] | Embedded Derivative Financial Instruments [Member]
Fair Value of Derivative Contracts:
Derivative Liability, Fair Value, Gross Liability	0	0
Other Current Liabilities [Member] | Cash Flow Hedging [Member] | Designated as Hedging Instrument [Member] | Foreign Exchange Contract [Member]
Fair Value of Derivative Contracts:
Derivative Liability, Fair Value, Gross Liability	$ 95	$ 56