Derivative Instruments and Hedging Activities (Details) (Not designated as a hedge, USD $) In Millions, unless otherwise specified	3 Months Ended		6 Months Ended	3 Months Ended	6 Months Ended				3 Months Ended		6 Months Ended
	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2014 Foreign currency exchange contracts Other income (expense), net	Jun. 30, 2014 Foreign currency exchange contracts Other income (expense), net	Jun. 30, 2013 Foreign currency exchange contracts Other income (expense), net	Jun. 30, 2014 Foreign currency forward contracts Other income (expense), net	Jun. 30, 2013 Foreign currency forward contracts Other income (expense), net	Jun. 30, 2014 Metal Contracts Cost of sales	Jun. 30, 2013 Metal Contracts Cost of sales	Jun. 30, 2013 Metal Contracts Cost of sales
Derivative instruments and hedging activities
Total gain (loss)	$ 2	$ (5)	$ (4)	$ (1)	$ (3)	$ 7	$ (1)	$ 2	$ 3	$ (5)	$ (9)