Schedule of Amounts Recognized in the Consolidated Balance Sheets (Details) - USD ($) $ in Thousands	Sep. 30, 2017	Dec. 31, 2016
Defined Benefit Plan, Amounts for Asset (Liability) Recognized in Statement of Financial Position [Abstract]
Plan assets in other long-term assets	$ 740	$ 654
Current portion of pension benefit obligation in wages and benefits payable	3,497	3,202
Long-term portion of pension benefit obligation	96,849	84,498
Pension benefit obligation, net	$ 99,606	$ 87,046

Amount of liability, recognized in statement of financial position, for defined benefit pension plan, classified as current. Excludes other postretirement benefit plan.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Amount of liability, recognized in statement of financial position, for defined benefit pension plan, classified as noncurrent. Excludes other postretirement benefit plan.

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Amount of asset, recognized in statement of financial position, for overfunded defined benefit pension and other postretirement plans.

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