Derivatives (Details 3) (USD $) In Millions, unless otherwise specified	Mar. 31, 2012	Dec. 31, 2011
Designated as Hedging Instrument [Member]
Location and amounts of derivative fair values in Consolidated Balance Sheets and derivative gains and losses in Consolidated Statements of Operations
Derivative Asset, Fair Value	$ 1.7	$ 0.1
Derivative Liability, Fair Value	2.3	11.5
Designated as Hedging Instrument [Member] | Commodity Futures Contracts [Member] | Other Assets Current [Member]
Location and amounts of derivative fair values in Consolidated Balance Sheets and derivative gains and losses in Consolidated Statements of Operations
Derivative Asset, Fair Value	1.2
Designated as Hedging Instrument [Member] | Commodity Futures Contracts [Member] | Other Assets Non Current [Member]
Location and amounts of derivative fair values in Consolidated Balance Sheets and derivative gains and losses in Consolidated Statements of Operations
Derivative Asset, Fair Value	0.5	0.1
Designated as Hedging Instrument [Member] | Commodity Futures Contracts [Member] | Other Liabilities Current [Member]
Location and amounts of derivative fair values in Consolidated Balance Sheets and derivative gains and losses in Consolidated Statements of Operations
Derivative Liability, Fair Value	1.0	9.4
Designated as Hedging Instrument [Member] | Commodity Futures Contracts [Member] | Other Liabilities Non Current [Member]
Location and amounts of derivative fair values in Consolidated Balance Sheets and derivative gains and losses in Consolidated Statements of Operations
Derivative Liability, Fair Value		0.3
Designated as Hedging Instrument [Member] | Interest Rate Swap [Member] | Other Liabilities Current [Member]
Location and amounts of derivative fair values in Consolidated Balance Sheets and derivative gains and losses in Consolidated Statements of Operations
Derivative Liability, Fair Value	1.3	1.8
Designated as Hedging Instrument [Member] | Interest Rate Swap [Member] | Other Liabilities Non Current [Member]
Location and amounts of derivative fair values in Consolidated Balance Sheets and derivative gains and losses in Consolidated Statements of Operations
Derivative Liability, Fair Value
Not Designated as Hedging Instrument [Member]
Location and amounts of derivative fair values in Consolidated Balance Sheets and derivative gains and losses in Consolidated Statements of Operations
Derivative Asset, Fair Value	0.3	1.2
Derivative Liability, Fair Value	0.7	2.1
Not Designated as Hedging Instrument [Member] | Foreign Currency Froward Contracts [Member] | Other Assets Current [Member]
Location and amounts of derivative fair values in Consolidated Balance Sheets and derivative gains and losses in Consolidated Statements of Operations
Derivative Asset, Fair Value	0.1	1.2
Not Designated as Hedging Instrument [Member] | Foreign Currency Froward Contracts [Member] | Other Liabilities Current [Member]
Location and amounts of derivative fair values in Consolidated Balance Sheets and derivative gains and losses in Consolidated Statements of Operations
Derivative Liability, Fair Value	0.1	0.1
Not Designated as Hedging Instrument [Member] | Commodity Futures Contracts [Member] | Other Assets Current [Member]
Location and amounts of derivative fair values in Consolidated Balance Sheets and derivative gains and losses in Consolidated Statements of Operations
Derivative Asset, Fair Value	0.1
Not Designated as Hedging Instrument [Member] | Commodity Futures Contracts [Member] | Other Assets Non Current [Member]
Location and amounts of derivative fair values in Consolidated Balance Sheets and derivative gains and losses in Consolidated Statements of Operations
Derivative Asset, Fair Value	0.1
Not Designated as Hedging Instrument [Member] | Commodity Futures Contracts [Member] | Other Liabilities Current [Member]
Location and amounts of derivative fair values in Consolidated Balance Sheets and derivative gains and losses in Consolidated Statements of Operations
Derivative Liability, Fair Value	0.6	1.8
Not Designated as Hedging Instrument [Member] | Commodity Futures Contracts [Member] | Other Liabilities Non Current [Member]
Location and amounts of derivative fair values in Consolidated Balance Sheets and derivative gains and losses in Consolidated Statements of Operations
Derivative Liability, Fair Value		0.2
Not Designated as Hedging Instrument [Member] | Interest Rate Swap [Member] | Other Liabilities Non Current [Member]
Location and amounts of derivative fair values in Consolidated Balance Sheets and derivative gains and losses in Consolidated Statements of Operations
Derivative Liability, Fair Value