Post-Retirement Benefit Plans - Benefit Obligation Activity (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018
Retirement Benefits [Abstract]
Retirement indemnity benefit obligation, beginning of year	$ 1,024	$ 1,303
Service cost	0	93
Interest cost	0	17
Plan amendment	0	0
Benefits paid	0	(12)
Curtailment gain	(1,000)	(148)
Actuarial loss	0	(178)
Exchange rate changes	(24)	(51)
Retirement indemnity benefit obligation, end of year	$ 0	$ 1,024

No definition available.

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- Definition

Amount of gain (loss) from change in actuarial assumptions which (increases) decreases benefit obligation of defined benefit plan. Assumptions include, but are not limited to, interest, mortality, employee turnover, salary, and temporary deviation from substantive plan.

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Amount of actuarial present value of benefits attributed to service rendered by employee for defined benefit plan.

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Amount of payment to participant of defined benefit plan which decreases benefit obligation. For pension plan, payment includes, but is not limited to, pension benefits and death benefits. For other postretirement plan, payment includes, but is not limited to, prescription drug benefits, health care benefits, life insurance benefits, and legal, educational and advisory services.

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Amount of (increase) decrease in benefit obligation of defined benefit plan from event reducing expected years of future service of present employees or eliminating accrual of benefits for some or all future services of present employees.

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

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Amount of cost recognized for passage of time related to defined benefit plan.

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Amount of increase (decrease) in benefit obligation of defined benefit plan from change in terms of existing plan or initiation of new plan.

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Amount of cost for actuarial present value of benefits attributed to service rendered by employee for defined benefit plan.

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