Defined Benefit Pension Plans - Level 3 Plan Asset Rollforward (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019
Defined Benefit Plan, Change in Fair Value of Plan Assets, Level 3 Reconciliation [Roll Forward]
Fair value of plan assets at January 1,	$ 12,665	$ 11,890
Effect of Foreign Currency	(177)	(237)
Fair value of plan assets at December 31,	10,206	12,665
Fair Value, Inputs, Level 3 [Member]
Defined Benefit Plan, Change in Fair Value of Plan Assets, Level 3 Reconciliation [Roll Forward]
Fair value of plan assets at January 1,	11,739	11,103
Net Realized and Unrealized Gains	354	1,096
Net Purchases, Issuances, Settlements, and Other	(46)	(187)
Release for Divestiture	(2,722)	0
Effect of Foreign Currency	(169)	(273)
Fair value of plan assets at December 31,	9,156	11,739
Insurance Fund [Member]
Defined Benefit Plan, Change in Fair Value of Plan Assets, Level 3 Reconciliation [Roll Forward]
Fair value of plan assets at January 1,	8,133
Fair value of plan assets at December 31,	9,156	8,133
Insurance Fund [Member] \| Fair Value, Inputs, Level 3 [Member]
Defined Benefit Plan, Change in Fair Value of Plan Assets, Level 3 Reconciliation [Roll Forward]
Fair value of plan assets at January 1,	8,133	8,020
Net Realized and Unrealized Gains	237	282
Net Purchases, Issuances, Settlements, and Other	15	(27)
Release for Divestiture	0	0
Effect of Foreign Currency	771	(142)
Fair value of plan assets at December 31,	9,156	8,133
Securities (Assets) [Member]
Defined Benefit Plan, Change in Fair Value of Plan Assets, Level 3 Reconciliation [Roll Forward]
Fair value of plan assets at January 1,	3,606
Fair value of plan assets at December 31,	0	3,606
Securities (Assets) [Member] \| Fair Value, Inputs, Level 3 [Member]
Defined Benefit Plan, Change in Fair Value of Plan Assets, Level 3 Reconciliation [Roll Forward]
Fair value of plan assets at January 1,	3,606	3,083
Net Realized and Unrealized Gains	117	814
Net Purchases, Issuances, Settlements, and Other	(61)	(160)
Release for Divestiture	(2,722)	0
Effect of Foreign Currency	(940)	(131)
Fair value of plan assets at December 31,	$ 0	$ 3,606

Amount, measured using unobservable inputs, of increase (decrease) in plan assets of defined benefit plan from actual return (loss) on assets still held.

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

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- Definition

Amount of asset segregated and restricted to provide benefit under defined benefit plan. Asset includes, but is not limited to, stock, bond, other investment, earning from investment, and contribution by employer and employee.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
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- Definition

Amount of foreign currency translation gain (loss) which increases (decreases) plan assets of defined benefit plan.

+ References

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- Definition

Amount, measured using unobservable input, of increase (decrease) in plan asset of defined benefit plan from purchase, sale and settlement of trade associated with underlying investment.

+ References

+ Details

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- Definition

Amount, measured using unobservable inputs, of increase (decrease) in plan assets of defined benefit plan, for assets transferred into (out of) Level 3 of fair value hierarchy. Includes, but is not limited to, transfer due to change in observability of significant inputs.

+ References

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