Balance Sheet Related Information (Details 5) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011
Accumulated other comprehensive income (loss)
Cumulative foreign currency translation	$ 6.0	$ 0.6
Prior service cost on pension plans (net of tax benefit of $0.1 in 2012 and $0.1 in 2011)	(0.2)	(0.2)
Net actuarial loss on pension plans (net of tax benefit of $7.8 in 2012 and $6.9 in 2011)	(12.0)	(11.9)
Unrealized loss on interest rate swap agreement (net of tax benefit of $3.3 in 2012 and $3.3 in 2011)	(5.1)	(5.7)
Unrealized gain on available-for-sale securities (net of tax expense of $1.2 in 2012 and $0 in 2011)	12.1	2.5
Accumulated other comprehensive income (loss)	$ 0.8	$ (14.7)