Pensions - Schedule of Amounts Associated with Pension Plans (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Retirement Benefits [Abstract]
Current liabilities	$ (1,442)	$ (1,409)
Long-term liabilities	(190,827)	(193,533)
Total pension liability as of December 31	$ (192,269)	$ (194,942)

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

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Period Type:	instant