Commitments and Contingencies (Details 3) (USD $)	12 Months Ended
	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Operating Leases, Annual minimum lease payments due [Abstract]
2012	$ 27,800,000
2013	24,300,000
2014	16,400,000
2015	8,600,000
2016	5,800,000
Thereafter	35,900,000
Rent expense
Rent expense	$ 40,700,000	$ 38,700,000	$ 43,400,000