Employee Benefit Plans - Summary of the Activity in the SERP's Projected Benefit Obligation (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Benefit obligation:
Balance, January 1	$ 122,035	$ 119,827
Service cost	1,002	4,329
Interest cost	3,076	3,908
Benefits paid	(2,968)	(2,793)
Actuarial (gain) loss	(5,822)	15,087
Balance, December 31	117,323	122,035	$ 119,827
SERP
Benefit obligation:
Balance, January 1	13,412	11,712
Service cost	147	121	97
Interest cost	291	347	408
Benefits paid	(282)	(291)	(262)
Actuarial (gain) loss	(1,148)	1,523
Balance, December 31	$ 12,420	$ 13,412	$ 11,712

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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- Definition

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

+ References

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

+ References

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- Definition

Amount of payment to participant under defined benefit plan which decreases plan assets. 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 for actuarial present value of benefits attributed to service rendered by employee for defined benefit plan.

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