Employee Benefit Plans (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2025	Jun. 30, 2024	Jun. 30, 2025	Jun. 30, 2024
Pension and SERPA Benefits:
Defined Benefit Plan Disclosure
Service cost	$ 963	$ 1,175	$ 1,926	$ 2,350
Interest cost	20,501	20,118	41,002	40,237
Expected return on plan assets	(32,799)	(33,143)	(65,598)	(66,286)
Amortization of unrecognized: Prior service cost (credit)	380	188	760	376
Amortization of unrecognized: Net (gain) loss	(174)	(163)	(348)	(326)
Special retirement benefit cost	0	1,722	0	1,722
Net periodic benefit income	(11,129)	(10,103)	(22,258)	(21,927)
Postretirement Healthcare Benefits:
Defined Benefit Plan Disclosure
Service cost	643	723	1,286	1,446
Interest cost	2,618	2,694	5,236	5,388
Expected return on plan assets	(4,675)	(4,424)	(9,350)	(8,848)
Amortization of unrecognized: Prior service cost (credit)	149	149	298	298
Amortization of unrecognized: Net (gain) loss	(1,369)	(1,250)	(2,738)	(2,500)
Net periodic benefit income	$ (2,634)	$ (2,108)	$ (5,268)	$ (4,216)