Consolidated Statements of Comprehensive Income Consolidated Statements of Comprehensive Income (Paranthetical) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Other Comprehensive Income (Loss), Foreign Currency Translation Gain (Loss) Arising During Period, Tax	$ 0	$ 0.1	$ 1.5
Other Comprehensive Income (Loss), Amortization, Pension and Other Postretirement Benefit Plans, Net Prior Service Cost Recognized in Net Periodic Pension Cost, Tax	(0.2)	0	9.3
Other Comprehensive Income (Loss), Reclassification, Pension and Other Postretirement Benefit Plans, Net Gain (Loss) Recognized in Net Periodic Benefit Cost, Tax	(0.2)	0	0.7
Other Comprehensive Income (Loss), Finalization of Pension and Non-Pension Postretirement Plan Valuation, Tax	0	0	2.2
Other Comprehensive Income (Loss), Unrealized Gain (Loss) on Derivatives Arising During Period, Tax	0.6	(0.1)	23.5
Other Comprehensive Income (Loss), Reclassification Adjustment on Derivatives Included in Net Income, Tax	$ 3.5	$ (1.7)	$ 22.6