Defined Benefit Pension Plans - Level 3 Plan Asset Rollforward (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018
Defined Benefit Plan, Change in Fair Value of Plan Assets, Level 3 Reconciliation [Roll Forward]
Fair value of plan assets at January 1,	$ 11,890	$ 12,834
Effect of Foreign Currency	(237)	(963)
Fair value of plan assets at December 31,	12,665	11,890
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,	11,103	12,045
Net Realized and Unrealized Gains	1,096	(35)
Net Purchases, Issuances, Settlements, and Other	(187)	0
Effect of Foreign Currency	(273)	(907)
Fair value of plan assets at December 31,	11,739	11,103
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,	8,020
Fair value of plan assets at December 31,	8,133	8,020
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,	8,020	8,384
Net Realized and Unrealized Gains	282	(158)
Net Purchases, Issuances, Settlements, and Other	(27)	141
Effect of Foreign Currency	(142)	(347)
Fair value of plan assets at December 31,	8,133	8,020
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,	3,083
Fair value of plan assets at December 31,	3,606	3,083
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,	3,083	3,661
Net Realized and Unrealized Gains	814	123
Net Purchases, Issuances, Settlements, and Other	(160)	(141)
Effect of Foreign Currency	(131)	(560)
Fair value of plan assets at December 31,	$ 3,606	$ 3,083

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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-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 20
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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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