Benefit Plans - Defined Benefit Plans - Change in Projected Benefit Obligation (Details) - Split-Dollar Life Insurance Benefit Plan - USD ($) $ in Thousands	3 Months Ended	9 Months Ended	12 Months Ended
Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020
Change in projected benefit obligation:
Projected benefit obligation at beginning of year			$ 9,689	$ 8,198	$ 8,198
Interest cost	$ 54	$ 62	164	$ 185	246
Actuarial loss					1,245
Projected benefit obligation at end of period	$ 9,853		$ 9,853		$ 9,689

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

+ Details

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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.

+ Details

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- Definition

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

+ References

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+ Details

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- Details

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