Financial Instruments, Derivatives and Hedging Activities (Details) (USD $) In Millions, unless otherwise specified	6 Months Ended			1 Months Ended
	Jun. 30, 2012 Commodity contracts M	Jun. 30, 2012 Foreign currency forward contracts	Jun. 30, 2012 Derivatives in Cash Flow Hedging Relationships Treasury Lock agreements (T-Locks)	Mar. 31, 2011 Fair value hedge Interest rate swaps 3.2% senior notes due 2015	Jun. 30, 2012 Fair value hedge Interest rate swaps 3.2% senior notes due 2015	Mar. 25, 2011 Fair value hedge Interest rate swaps 3.2% senior notes due 2015	Jun. 30, 2012 Fair value hedge Foreign currency forward contracts
Financial instruments, derivatives and hedging activities
Maturity period of price risk derivative, low end of range (in months)	12
Maturity period of price risk derivative, high end of range (in months)	18
Debt, fixed interest rate (as a percent)						3.20%
Debt, face amount						$ 350
Debt, fixed interest rate (as a percent)						3.20%
Fair value of interest rate swap agreements					21
Debt, floating rate of interest basis				six-month US dollar LIBOR
Losses on cash flow hedges			11
Losses on cash flow hedges, income tax effect			7
Accumulated losses (gains) from derivative instruments	6	(1)
Accumulated losses from commodity-hedging derivative instruments, tax effect	3
Net notional foreign currency forward contracts							134
Fair value of foreign currency forward contracts							$ 2