Consolidated Statements of Comprehensive Income (Loss) (Parenthetical) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Statement of Other Comprehensive Income [Abstract]
Tax expense (benefit) on current period cash flow hedging activity	$ 2.4	$ 0.2	$ (3.3)
Tax expense on reclassification of hedging activities into earnings	2.7	2.6	4.2
Tax benefit on current period pension and postretirement plan adjustment	(1.6)	(7.3)	(1.6)
Tax expense on reclassification of pension and postretirement into earnings	$ 2.0	$ 1.8	$ 1.3