Defined Benefit Pension Plans - Schedule of Amounts Recognized in Other Comprehensive Income (loss), pre-tax (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Retirement Benefits [Abstract]
Net actuarial (gain) loss	$ 8,734	$ 8,762	$ (3,191)
Settlement (gain) loss	(286)	(250)	(1)
Curtailment (gain) loss	0	0	(1)
Plan asset (gain) loss	64	(526)	724
Amortization of net actuarial loss	(2,255)	(1,648)	(1,533)
Amortization of prior service cost	(68)	(68)	(61)
Other	0	(160)	124
Other comprehensive (income) loss	$ 6,189	$ 6,110	$ (3,939)

OCI, Defined Benefit Plan, Curtailment

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- Definition

(Gain) Loss recognized in other comprehensive income (but not yet recognized in net periodic benefit cost) arising during the period.

+ References

No definition available.

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Pretax change in the value of the plan assets resulting from experience different from that assumed that has not been recognized in net periodic benefit cost.

+ References

No definition available.

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Amount, before tax, of reclassification adjustment from accumulated other comprehensive (income) loss for prior service cost (credit) of defined benefit plan.

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Amount, before tax, of increase (decrease) to other comprehensive income from settlement and curtailment gain (loss) of defined benefit plan.

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Amount, before tax, after reclassification adjustment, of (increase) decrease in accumulated other comprehensive income for defined benefit plan.

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Amount, before tax, of gain (loss) for (increase) decrease in value of benefit obligation for change in actuarial assumptions and increase (decrease) in value of plan assets from experience different from that assumed of defined benefit plan, that has not been recognized in net periodic benefit (cost) credit.

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Amount, before tax, of reclassification adjustment from accumulated other comprehensive income (loss) for gain (loss) of defined benefit plan.

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