Retirement Plans, Other Changes in Plan Assets (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Defined Benefit Plan Disclosure [Line Items]
Amortization of prior service cost	$ (148)	$ (148)	$ (148)
Amortization of actuarial loss	25,519	7,780	16,296
Income tax (expense)	(7,803)	(3,064)	(4,465)
Other comprehensive income on pension and postretirement obligations	23,656	8,465	$ 12,158
RAP
Defined Benefit Plan Disclosure [Line Items]
Net actuarial gain	25,257	8,209
Amortization of prior service cost	(73)	(73)
Amortization of actuarial loss	4,594	3,897
Other Comprehensive (Income) Loss, Defined Benefit Plan, Prior Service Cost (Credit), before Tax	1,494	0
Income tax (expense)	(7,791)	(3,040)
Other comprehensive income on pension and postretirement obligations	23,480	8,993
Postretirement Plan
Defined Benefit Plan Disclosure [Line Items]
Net actuarial gain	119	169
Amortization of prior service cost	(75)	(75)
Amortization of actuarial loss	0	0
Other Comprehensive (Income) Loss, Defined Benefit Plan, Prior Service Cost (Credit), before Tax	0	0
Income tax (expense)	(11)	(23)
Other comprehensive income on pension and postretirement obligations	$ 33	$ 71