Pension and Other Postretirement Benefit Plans - Amounts Recognized In AOCI on a Pre-tax Basis (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Net Actuarial loss (gain)	$ 1,906	$ 2,834	$ 1,628
Prior Service cost (credit)	(27)	(112)	(198)
Total	1,879	2,722	1,430
Retirement Plan [Member]
Net Actuarial loss (gain)	1,414	1,775	2,273
Prior Service cost (credit)	0	0	0
Total	1,414	1,775	2,273
Other Postretirement Benefits Plan [Member]
Net Actuarial loss (gain)	932	1,333	(265)
Prior Service cost (credit)	(27)	(112)	(198)
Total	905	1,221	(463)
Directors' Plan [Member]
Net Actuarial loss (gain)	(440)	(274)	(380)
Prior Service cost (credit)	0	0	0
Total	$ (440)	$ (274)	$ (380)

Amount, before tax, of accumulated other comprehensive (income) loss for defined benefit plan, that has not been recognized in net periodic benefit cost (credit).

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Amount, before tax, of accumulated other comprehensive income (loss) for gain (loss) of defined benefit plan, that has not been recognized in net periodic benefit (cost) credit.

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-Publisher FASB
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Amount, before tax, of accumulated other comprehensive (income) loss for cost (credit) of benefit change attributable to participants' prior service from plan amendment or plan initiation of defined benefit plan, that has not been recognized in net periodic benefit cost (credit).

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