Commitments and Contingencies (Details Textual) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Commitments and Contingencies (Additional Textual) [Abstract]
Rental expense for operating leases	$ 13.6	$ 14.8	$ 15.4
Sublease income	0.6	0.9	1.0
One-time payment for operating lease expense		0.9
Future remediation cost	0.6
Maximum [Member]
Commitments and Contingencies (Textual) [Abstract]
Estimated remediation cost	$ 0.5	$ 0.5	$ 0.2