Lease Commitments (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2012
Schedule of Future minimum cash commitments under operating leases
Gross Operating Lease Commitments, 2013	$ 37,167
Gross Operating Lease Commitments, 2014	29,976
Gross Operating Lease Commitments, 2015	25,900
Gross Operating Lease Commitments, 2016	22,876
Gross Operating Lease Commitments, 2017	16,956
Gross Operating Lease Commitments, Thereafter	25,940
Gross Operating Lease Commitments, Total	158,815
Sub-Leases, 2013	1,372
Sub-Leases, 2014	1,084
Sub-Leases, 2015	875
Sub-Leases, 2016	699
Sub-Leases, 2017
Sub-Leases, Thereafter
Sub-Leases, Total	4,030
Net Operating Lease Commitments, 2013	35,795
Net Operating Lease Commitments, 2014	28,892
Net Operating Lease Commitments, 2015	25,025
Net Operating Lease Commitments, 2016	22,177
Net Operating Lease Commitments, 2017	16,956
Net Operating Lease Commitments , Thereafter	25,940
Net Operating Lease Commitments, Total	$ 154,785