Commitments and Contingencies Future minimum lease payments for financing transactions (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2012
Leases [Abstract]
Minimum Lease Payments, Capital Leases, Next Twelve Months	$ 3,254
Minimum Lease Payments, Capital Leases, within Two Years	3,328
Minimum Lease Payments, Capital Leases, within Three Years	3,410
Minimum Lease Payments, Capital Leases, within Four Years	3,493
Minimum Lease Payments, Capital Leases, within Five Years	3,615
Minimum Lease Payments, Capital Leases, Thereafter	8,278
Minimum Lease Payments, Capital Leases	25,378
Interest Portion of Minimum Lease Payments, Sale Leaseback Transactions	(5,186)
Capital Leases, Future Minimum Payments, Present Value of Net Minimum Payments	20,192
Other Long-term Debt, Current	2,056
Other Long-term Debt, Noncurrent	$ 18,136

Other Long-term Debt, Current, Building leases

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Present value of minimum lease payments for capital leases net of executory costs, including amounts paid by the lessee to the lessor for insurance, maintenance and taxes.

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Amount necessary to reduce minimum lease payments to present value for sale-leaseback transactions accounted for using the deposit method or as a financing.

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Amount of minimum lease payments for sale-leaseback transactions accounted for using the deposit method or as a financing.

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Amount of minimum lease payments maturing after the fifth fiscal year following the latest fiscal year for sale-leaseback transactions accounted for using the deposit method or as a financing.

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Amount of minimum lease payments maturing in the fifth fiscal year following the latest fiscal year for sale-leaseback transactions accounted for using the deposit method or as a financing.

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Amount of minimum lease payments maturing in the fourth fiscal year following the latest fiscal year for sale-leaseback transactions accounted for using the deposit method or as a financing.

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Amount of minimum lease payments maturing in the next fiscal year following the latest fiscal year for sale-leaseback transactions accounted for using the deposit method or as a financing.

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Amount of minimum lease payments maturing in the third fiscal year following the latest fiscal year for sale-leaseback transactions accounted for using the deposit method or as a financing.

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Amount of minimum lease payments maturing in the second fiscal year following the latest fiscal year for sale-leaseback transactions accounted for using the deposit method or as a financing.

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