Derivative Instruments (Details 2) (USD $) In Millions, unless otherwise specified	Mar. 31, 2012	Dec. 31, 2011	Mar. 31, 2011
Derivatives, Fair Value
Total asset derivatives	$ 9	$ 13	$ 11
Total liability derivatives	10	10	17
Derivatives designated as hedging instruments | Commodity futures contracts | Other liabilities (current)
Derivatives, Fair Value
Total liability derivatives	6	6	2
Derivatives not designated as hedging instruments
Derivatives, Fair Value
Total asset derivatives	9	13	11
Derivatives not designated as hedging instruments | Foreign exchange contracts | Receivables
Derivatives, Fair Value
Total asset derivatives	8	13	6
Derivatives not designated as hedging instruments | Foreign exchange contracts | Deposits, receivables, and other assets
Derivatives, Fair Value
Total asset derivatives			4
Derivatives not designated as hedging instruments | Foreign exchange contracts | Other liabilities (current)
Derivatives, Fair Value
Total asset derivatives	1		1
Total liability derivatives	$ 4	$ 4	$ 15