Pension Plans and Other Postretirement Benefits (Details6) (USD $) In Millions, unless otherwise specified	Dec. 31, 2011	Dec. 31, 2010
Pension Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Prepaid pension asset	$ 0	$ 8.7
Current liabilities	(8.7)	(6.6)
Noncurrent liabilities	(508.9)	(58.3)
Defined Benefit Plan, Amounts Recognized in Balance Sheet, Total	(517.6)	(56.2)
Other Postretirement Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Current liabilities	(71.7)	(63.3)
Noncurrent liabilities	(488.1)	(423.8)
Defined Benefit Plan, Amounts Recognized in Balance Sheet, Total	$ (559.8)	$ (487.1)