Disclosures About Derivative Instruments and Hedging Activities (Details 2) (USD $) In Millions, unless otherwise specified	Sep. 30, 2012	Dec. 31, 2011
Designated as Hedging Instrument [Member] | Commodity Contract [Member] | Other Current Assets [Member]
Derivatives, Fair Value [Line Items]
Derivative asset (liability), fair value	$ 0.5	$ 0
Designated as Hedging Instrument [Member] | Commodity Contract [Member] | Accrued Liabilities [Member]
Derivatives, Fair Value [Line Items]
Derivative asset (liability), fair value	(9.2)	(19.4)
Designated as Hedging Instrument [Member] | Commodity Contract [Member] | Other Noncurrent Liabilities [Member]
Derivatives, Fair Value [Line Items]
Derivative asset (liability), fair value	(0.2)	0
Not Designated as Hedging Instrument [Member] | Commodity Contract [Member] | Other Current Assets [Member]
Derivatives, Fair Value [Line Items]
Derivative asset (liability), fair value	0.2	0
Not Designated as Hedging Instrument [Member] | Commodity Contract [Member] | Accrued Liabilities [Member]
Derivatives, Fair Value [Line Items]
Derivative asset (liability), fair value	(0.9)	(2.2)
Not Designated as Hedging Instrument [Member] | Foreign Exchange Contract [Member] | Other Current Assets [Member]
Derivatives, Fair Value [Line Items]
Derivative asset (liability), fair value	0	1.0
Not Designated as Hedging Instrument [Member] | Foreign Exchange Contract [Member] | Accrued Liabilities [Member]
Derivatives, Fair Value [Line Items]
Derivative asset (liability), fair value	$ (0.5)	$ 0