Balance Sheet Related Information (Details Textual) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011
Balance Sheet Related Information (Textual) [Abstract]
Pension adjustments, net of tax	$ 0.1	$ 0.1
Tax benefit on actuarial loss on pension plans	7.8	6.9
Tax benefit on unrealized loss on interest rate swap agreement	3.3	3.3
Tax benefit (expense) on unrealized gain on available-for-sale securities	$ 1.2	$ 0