Schedule of Amounts Recognized in the Consolidated Balance Sheets (Details) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
Defined Benefit Plan [Abstract]
Plan assets in other long-term assets	$ 576	$ 572
Current portion of pension benefit obligation in wages and benefits payable	2,890	2,730
Long-term portion of pension benefit obligation	90,925	91,522
Pension benefit obligation, net	$ 93,239	$ 93,680

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

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