Accumulated Other Comprehensive Income (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Foreign Currency Translation:
Balance at beginning of period	$ 161.1	$ 175.8	$ 167.5
Other comprehensive income	9.2	(14.7)	8.3
Balance at end of period	170.3	161.1	175.8
Unrealized Losses on Cash Flow Hedges
Balance at beginning of period	(1.1)	(3.0)	(3.5)
Other comprehensive income	(0.2)	(0.3)	(2.1)
Realized loss on reclassification	1.3	2.2	2.6
Balance at end of period		(1.1)	(3.0)
Pension Liability Adjustment
Balance at beginning of period	(17.5)	(20.4)	(10.5)
Other comprehensive income	(16.1)	1.6	(10.5)
Realized loss on reclassification	1.1	1.3	0.6
Balance at end of period	(32.5)	(17.5)	(20.4)
Accumulated Other Comprehensive Income
Balance at beginning of period	142.5	152.4	153.5
Other comprehensive income	(7.1)	(13.4)	(4.3)
Realized loss on reclassification	2.4	3.5	3.2
Balance at end of period	$ 137.8	$ 142.5	$ 152.4