Commitments and Contingencies (Schedule of Lease Commitments) (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2011
Commitments and Contingencies Disclosure [Abstract]
2012	$ 59,925
2013	53,600
2014	50,138
2015	37,051
2016	31,036
Thereafter	29,573
Total operating leases	261,323
Sublease income, 2012	779
Sublease income, 2013	736
Sublease income, 2014	539
Sublease income, 2015	539
Sublease income, 2016	539
Sublease income, thereafter	90
Sublease income, total	$ 3,222

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The total of future contractually required payments on leases defined as operating.

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