Benefit Plans - Defined Benefit Plans - Change in Projected Benefit Obligation (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended	12 Months Ended
Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019	Dec. 31, 2019
Split-Dollar Life Insurance Benefit Plan
Change in projected benefit obligation:
Projected benefit obligation at beginning of year			$ 8,198	$ 6,903	$ 6,903
Interest cost	$ 62	$ 69	185	209	278
Actuarial loss (gain)			(42)		1,017
Projected benefit obligation at end of period	8,341		8,341		$ 8,198
Supplemental Retirement Plan
Change in projected benefit obligation:
Interest cost	$ 234	$ 264	$ 701	$ 792

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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