Commitments and Contingencies Minimum Operating Lease Payments (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2013
Operating Lease Commitments:
Operating lease commitments, 2014	$ 8,759
Operating lease commitments, 2015	6,006
Operating lease commitments, 2016	4,938
Operating lease commitments, 2017	4,347
Operating lease commitments, 2018	3,383
Operating lease commitments, Thereafter	4,472
Operating lease commitments	31,905
Sublease Commitments:
Sublease rental income, 2014	720
Sublease rental income, 2015	420
Sublease rental income, 2016	0
Sublease rental income, 2017	0
Sublease rental income, 2018	0
Sublease rental income, Thereafter	0
Sublease rental income	1,140
Operating commitments, net:
Operating commitments, net, 2014	8,039
Operating commitments, net, 2015	5,586
Operating commitments, net, 2016	4,938
Operating commitments, net, 2017	4,347
Operating commitments, net, 2018	3,383
Operating commitments, net, Thereafter	4,472
Operating commitments, net	30,765
Purchase commitments:
Purchase commitments, 2014	37,794
Purchase commitments, 2015	0
Purchase commitments, 2016	0
Purchase commitments, 2017	0
Purchase commitments, 2018	0
Purchase commitments, Thereafter	0
Purchase commitments	37,794
Other contract commitments:
Other contract commitments, 2014	9,632
Other contract commitments, 2015	173
Other contract commitments, 2016	50
Other contract commitments, 2017	41
Other contract commitments, 2018	50
Other contract commitments, Thereafter	0
Other contract commitments	9,946
Contractual Obligation, Due in Third Year	4,988
Contractual Obligation	78,505
Contractual Obligation, Due in Next Twelve Months	55,465
Contractual Obligation, Due in Second Year	5,759
Contractual Obligation, Due in Fourth Year	4,388
Contractual Obligation, Due in Fifth Year	3,433
Contractual Obligation, Due after Fifth Year	$ 4,472

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