Leasing Obligations - Schedule of Future Minimum Lease Payments (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2011
Capital Leases
2012	$ 122
2013	59
2014	19
2015	0
2016	0
Thereafter	0
Total minimum lease payments	200
Less amount representing interest	(17)
Present value of net minimum capital lease payments	183
Less current portion	(112)
Obligations under capital leases, excluding current installments	71
Operating Leases
2012	44,316
2013	31,173
2014	20,876
2015	15,338
2016	10,078
Thereafter	42,210
Total minimum lease payments	$ 163,991

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Amount equal to the present value (the principal) at the beginning of the lease term of minimum lease payments during the lease term (excluding that portion of the payments representing executory costs such as insurance, maintenance, and taxes to be paid by the lessor, together with any profit thereon) net of payments or other amounts applied to the principal, through the balance sheet date and due to be paid within one year (or one operating cycle, if longer) of the balance sheet date.