Retirement Plans and Other Postretirement Benefits - Schedule of Net Periodic Benefit Costs and Portion including Portion Charged to Expense (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2025	Jun. 30, 2024	Jun. 30, 2025	Jun. 30, 2024
Amortization of:
Portion of costs (credits) charged to expense	$ (3,692)	$ (12,877)	$ (6,650)	$ (24,445)
Pension Plans
Defined Benefit Plan Disclosure [Line Items]
Service cost-benefits earned during the period	11,127	11,190	22,076	21,821
Non-service costs (credits):
Interest cost on benefit obligation	38,584	37,085	77,560	74,321
Expected return on plan assets	(44,849)	(47,342)	(89,396)	(94,325)
Amortization of:
Prior service credit	0	0	0	0
Net actuarial loss (gain)	11,248	10,014	23,366	20,958
Net periodic benefit costs (credits)	16,110	10,947	33,606	22,775
Portion of costs (credits) charged to expense	9,365	5,500	19,826	11,837
Other Benefits Plans
Defined Benefit Plan Disclosure [Line Items]
Service cost-benefits earned during the period	2,059	2,518	4,041	4,977
Non-service costs (credits):
Interest cost on benefit obligation	5,070	5,472	10,172	11,085
Expected return on plan assets	(12,142)	(11,708)	(24,284)	(23,417)
Amortization of:
Prior service credit	0	(9,447)	(1,265)	(18,894)
Net actuarial loss (gain)	(2,965)	(2,258)	(5,864)	(4,338)
Net periodic benefit costs (credits)	(7,978)	(15,423)	(17,200)	(30,587)
Portion of costs (credits) charged to expense	$ (6,399)	$ (11,515)	$ (13,272)	$ (22,821)