Pension Plans and Other Postretirement Benefits (Details-6) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Expected Cash Flows
Expected employer contributions, 2022	$ 0
Cash contributions to pension and other postretirement plans	6,935	$ 6,296	$ 5,714
Pension Benefits [Member]
Benefit Payments, Gross
Defined benefit plan expected future benefit payments, 2022	19,736
Defined benefit plan expected future benefit payments, 2023	20,474
Defined benefit plan expected future benefit payments, 2024	21,197
Defined benefit plan expected future benefit payments, 2025	21,897
Defined benefit plan expected future benefit payments, 2026	22,497
Defined benefit plan expected future benefit payments, 2027-2031	117,862
Postretirement Benefits [Member]
Benefit Payments, Gross
Defined benefit plan expected future benefit payments, 2022	4,713
Defined benefit plan expected future benefit payments, 2023	4,982
Defined benefit plan expected future benefit payments, 2024	5,281
Defined benefit plan expected future benefit payments, 2025	5,533
Defined benefit plan expected future benefit payments, 2026	5,567
Defined benefit plan expected future benefit payments, 2027-2031	27,651
Medicare Part D Subsidies
Expected Medicare Part D Subsidies, 2022	(304)
Expected Medicare Part D Subsidies, 2023	(333)
Expected Medicare Part D Subsidies, 2024	(363)
Expected Medicare Part D Subsidies, 2025	(395)
Expected Medicare Part D Subsidies, 2026	(430)
Expected Medicare Part D Subsidies, 2027-2031	(2,541)
Defined benefit plan expected net future benefit payments, 2022	4,409
Defined benefit plan expected net future benefit payments, 2023	4,649
Defined benefit plan expected net future benefit payments, 2024	4,918
Defined benefit plan expected net future benefit payments, 2025	5,138
Defined benefit plan expected net future benefit payments, 2026	5,137
Defined benefit plan expected net future benefit payments, 2027-2031	$ 25,110