Employee Benefit and Deferred Compensation Plans - Plan Expense for Non-Contributory Benefit Pension Plan and Post-Retirement Health and Life Plans (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
Pension Benefits
Plan expense for noncontributory benefit pension plan and post-retirement health and life plans
Service cost	$ 0	$ 0
Interest cost	249	184
Expected return on plan assets	(309)	(421)
Recognized actuarial loss (gain)	131	61
Net periodic benefit cost (return)	71	(176)
Other Benefits
Plan expense for noncontributory benefit pension plan and post-retirement health and life plans
Service cost	0	1
Interest cost	6	3
Expected return on plan assets	0	0
Recognized actuarial loss (gain)	(15)	(19)
Net periodic benefit cost (return)	$ (9)	$ (15)