Pension Benefits - Benefit obligations (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019
Pension Benefits
Projected benefit obligation at beginning of the year	$ 4,611	$ 2,591
Service cost	492	289
Interest cost	249	194
Actuarial loss (gain)	505	1,720
Foreign currency exchange rates changes	168	52
Benefits paid	(85)	(235)
Projected benefit obligation at end of the year	$ 5,940	$ 4,611

No definition available.

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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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- Definition

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

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