Retirement Plans, Components of Net Periodic Benefit Cost, Other Postretirement Benefits (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Other changes in benefit obligations recognized in other comprehensive income [Abstract]
Recognition of actuarial gain	$ (58,147)	$ (44,491)	$ 31,755
Other Postretirement Benefits [Member]
Components of net periodic benefit cost [Abstract]
Interest cost	17	17	22
Amortization of actuarial gain	(394)	(451)	(522)
Net periodic benefit cost	377	(434)	(500)
Other changes in benefit obligations recognized in other comprehensive income [Abstract]
Current year actuarial loss (gain)	(58)	104	84
Recognition of actuarial gain	394	451	522
Total recognized in other comprehensive income	336	555	606
Total recognized in net periodic benefit cost and other comprehensive income	$ 41	$ 121	$ 106