Income Taxes (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Current Income Tax Expense (Benefit), Continuing Operations [Abstract]
Federal	$ 47.5	$ 41.4	$ 59.7
State	7.3	5.3	8.6
Foreign	13.4	7.3	5.6
Total current	68.2	54.0	73.9
Deferred Income Tax Expense (Benefit), Continuing Operations [Abstract]
Federal	0.7	0.4	(4.5)
State	(0.2)	(1.0)	(3.2)
Foreign	(2.0)	2.4	(1.4)
Total deferred	(1.5)	1.8	(9.1)
Total income tax provision	$ 66.7	$ 55.8	$ 64.8