Commitments and Contingencies (Schedule of Future Minimum Rental Payments and Receipts for Leases) (Details) $ in Thousands	Dec. 31, 2017 USD ($)
Commitments and Contingencies Disclosure [Abstract]
Rental Payments, 2017	$ 29,181
Rental Payments, 2018	28,035
Rental Payments, 2019	26,254
Rental Payments, 2020	24,552
Rental Payments, 2021	20,885
Rental Payments, Thereafter	77,541
Rental Payments, Total	206,448
Rental Receipts, 2017	717
Rental Receipts, 2018	592
Rental Receipts, 2019	488
Rental Receipts, 2020	395
Rental Receipts, 2021	353
Rental Receipts, Thereafter	1,438
Rental Receipts, Total	$ 3,983

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Amount of required minimum rental payments for leases having an initial or remaining non-cancelable letter-terms in excess of one year.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 840
-SubTopic 10
-Section 55
-Paragraph 40
-Subparagraph (Note 3)
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Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Future minimum rental payments in aggregate as of the balance sheet date under operating leases.

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Future minimum lease payments receivable under operating leases for periods greater than five years following the balance sheet date.

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