Derivatives (Details 4) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Cash Flow Hedging [Member]
Amount of Loss or (Gain) Reclassified from AOCI into Income (Effective Portion):
Effective portion	$ (9.6)	$ (8.8)	$ 20.9
Cash Flow Hedging [Member] | Cost of Goods Sold [Member] | Commodity Futures Contracts [Member]
Amount of Loss or (Gain) Reclassified from AOCI into Income (Effective Portion):
Effective portion	(12.1)	(11.2)	19.6
Cash Flow Hedging [Member] | Interest Expense Net [Member] | Interest Rate Swap [Member]
Amount of Loss or (Gain) Reclassified from AOCI into Income (Effective Portion):
Effective portion	2.5	2.4	1.3
Cash Flow Hedging [Member] | Losses and Other Expenses Net [Member] | Commodity Futures Contracts [Member]
Amount of (Gain) or Loss Recognized in Income on Derivatives (Ineffective Portion):
Ineffective portion	0.1	(0.4)	(0.1)
Not Designated as Hedging Instrument [Member]
Amount of (Gain) or Loss Recognized in Income on Derivatives:
Amount of (Gain) or Loss Recognized in Income on Derivatives	3.8	(1.9)	(0.3)
Not Designated as Hedging Instrument [Member] | Losses and Other Expenses Net [Member] | Foreign Currency Froward Contracts [Member]
Amount of (Gain) or Loss Recognized in Income on Derivatives:
Amount of (Gain) or Loss Recognized in Income on Derivatives	0.3	(0.2)	3.1
Not Designated as Hedging Instrument [Member] | Losses and Other Expenses Net [Member] | Commodity Futures Contracts [Member]
Amount of (Gain) or Loss Recognized in Income on Derivatives:
Amount of (Gain) or Loss Recognized in Income on Derivatives	$ 3.5	$ (1.7)	$ (3.4)