Derivative Instruments (Details) In Millions, unless otherwise specified	3 Months Ended		6 Months Ended			3 Months Ended		6 Months Ended
	Jun. 30, 2012 USD ($)	Jun. 30, 2011 USD ($)	Jun. 30, 2012 USD ($)	Jun. 30, 2011 USD ($)	Dec. 31, 2004 EUR (€)	Jun. 30, 2012 Commodity futures contracts Cash Flow Hedges USD ($) mmbtu	Jun. 30, 2011 Commodity futures contracts Cash Flow Hedges USD ($) mmbtu	Jun. 30, 2012 Commodity futures contracts Cash Flow Hedges USD ($) mmbtu	Jun. 30, 2011 Commodity futures contracts Cash Flow Hedges USD ($) mmbtu	Jun. 30, 2012 Commodity futures contracts Cash Flow Hedges Maximum	Jun. 30, 2012 Commodity futures contracts Cash Flow Hedges Minimum
Derivatives and Hedges
Coverage of commodity futures contracts (in MM BTUs)						6,200,000	6,300,000	6,200,000	6,300,000
Unrecognized loss included in Accumulated OCI						$ (3)	$ (2)	$ (3)	$ (2)
Period during which unrecognized loss included in Accumulated OCI will be reclassified into earnings (in months)										24 months	12 months
Commodity futures contracts loss recognized in OCI						1	(1)	(2)	(2)
Commodity futures contracts loss reclassified from accumulated OCI into income						(2)	(1)	(5)	(3)
Senior notes designated as net investment hedge					225
Net investment hedge gain (loss) recognized in OCI		(7)		(25)
Forward exchange and option agreements in various currencies	590	890	590	890
Foreign exchange contracts gain (loss) recognized in income	$ 9	$ (17)	$ 10	$ (24)