Pension and Other Postretirement Benefit Plans - Change in Benefit Obligation and Assets (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Retirement Plan [Member]
Projected benefit obligation at beginning of year	$ 24,227	$ 22,443
Interest cost	512	652
Actuarial (gain) loss	(1,562)	2,109
Benefits paid	(1,068)	(977)
Projected benefit obligation at end of year	22,109	24,227
Market value of assets at beginning of year	27,720	25,505
Actual return on plan assets	(593)	3,192
Benefits paid	(1,068)	(977)
Market value of plan assets at end of year	26,059	27,720
Accrued pension asset/liability included in other assets	3,950	3,493
Other Postretirement Benefits Plan [Member]
Projected benefit obligation at beginning of year	10,799	8,762
Service cost	293	274
Interest cost	233	259
Actuarial (gain) loss	(370)	1,599
Benefits paid	(102)	(95)
Projected benefit obligation at end of year	10,853	10,799
Market value of assets at beginning of year	0	0
Benefits paid	(102)	(95)
Market value of plan assets at end of year	0	0
Employer contributions	102	95
Accrued pension cost included in other liabilities	10,853	10,799
Directors' Plan [Member]
Projected benefit obligation at beginning of year	2,276	2,290
Service cost	16	15
Interest cost	46	64
Actuarial (gain) loss	(184)	51
Benefits paid	(144)	(144)
Projected benefit obligation at end of year	2,010	2,276
Market value of assets at beginning of year	0	0
Benefits paid	(144)	(144)
Market value of plan assets at end of year	0	0
Employer contributions	144	144
Accrued pension cost included in other liabilities	$ 2,010	$ 2,276