Retirement Savings Plans	12 Months Ended
Dec. 31, 2011
Retirement Savings Plans [Abstract]
Retirement Savings Plans	14. Retirement Savings Plans The Company, through its U.S. and U.K. subsidiaries, offers its employees the opportunity to invest in defined contribution plans. For the years ended December 31, 2011, 2010 and 2009, the Company contributed $1.2 million, $0.9 million and $0.6 million, respectively, to the plans.

The entire disclosure for pension and other postretirement benefits.

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