Financial Instruments (Fair Value of Derivative Instruments) (Details) (Foreign Exchange Forward, USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2013
Derivatives, Fair Value [Line Items]
Gain (loss) on derivative contracts not designated as hedging instruments	$ 27
Not Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Total foreign currency forward-exchange contracts	5
Not Designated as Hedging Instrument | Other Current Assets
Derivatives, Fair Value [Line Items]
Foreign currency forward-exchange contracts	10
Not Designated as Hedging Instrument | Other Current Liabilities
Derivatives, Fair Value [Line Items]
Foreign currency forward-exchange contracts	$ (5)