Retirement Plans and Other Postretirement Benefits - Components of Net Periodic Benefit Cost (Income) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Retirement Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost	$ 136	$ 142	$ 266	$ 279
Interest cost	587	397	1,184	787
Expected loss on plan assets	(761)	(945)	(1,531)	(1,878)
Amortization of net actuarial loss (gain)	250	205	500	409
Net periodic benefit cost (income)	212	(201)	419	(403)
Other Post Retirement Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost	19	32	38	62
Interest cost	32	24	64	48
Expected loss on plan assets	0	0	0	0
Amortization of net actuarial loss (gain)	(4)	13	(8)	27
Net periodic benefit cost (income)	$ 47	$ 69	$ 94	$ 137