Pension Plans and Other Postretirement Benefits (Details-2) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Pension Benefits [Member]
Components of Net Periodic Benefit Cost [Abstract]
Service cost	$ 2,612	$ 3,078	$ 2,892
Interest cost	17,139	17,118	17,319
Expected return on assets	(29,014)	(28,597)	(25,248)
Settlement cost	0	0	0
Amortization of:
Transition obligation	0	0	0
Prior service (credit) cost	0	0	0
Actuarial loss	299	859	1,760
Net periodic benefit cost (credit)	(8,964)	(7,542)	(3,277)
Postretirement Benefits [Member]
Components of Net Periodic Benefit Cost [Abstract]
Service cost	743	856	780
Interest cost	3,028	3,126	3,308
Expected return on assets	(2,715)	(2,725)	(2,595)
Settlement cost	0	288	0
Amortization of:
Transition obligation	3	3	3
Prior service (credit) cost	0	(242)	0
Actuarial loss	(642)	380	(190)
Net periodic benefit cost (credit)	$ 417	$ 1,686	$ 1,306