Retirement Plans and Other Postretirement Benefits - Schedule of Changes Benefit Obligations and Funded Status (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Pension Plans
Change in Benefit Obligation
Benefit obligation at the beginning of the period	$ 2,792,309	$ 2,908,063
Service cost	44,153	43,641	$ 39,461
Interest cost	155,121	148,643	153,561
Benefit payments	(226,888)	(216,238)
Actuarial (gain) loss	79,363	(91,800)
Other plan changes	6,752	0
Benefit obligation at the end of the period	2,850,810	2,792,309	2,908,063
Change in Plan Assets
Balance at the beginning of the period	2,639,862	2,835,549
Actual return on plan assets	244,343	4,518
Benefit payments	(213,684)	(200,205)
Balance at the end of the period	2,670,521	2,639,862	2,835,549
Funded/(Underfunded) Status at the end of the period	(180,289)	(152,447)
Other Benefits Plans
Change in Benefit Obligation
Benefit obligation at the beginning of the period	360,090	430,434
Service cost	8,081	9,955	8,567
Interest cost	20,345	22,169	22,509
Benefit payments	(28,293)	(30,516)
Actuarial (gain) loss	7,759	(71,952)
Other plan changes	0	0
Benefit obligation at the end of the period	367,982	360,090	430,434
Change in Plan Assets
Balance at the beginning of the period	702,192	696,494
Actual return on plan assets	65,124	32,816
Benefit payments	0	(27,118)
Balance at the end of the period	767,316	702,192	$ 696,494
Funded/(Underfunded) Status at the end of the period	$ 399,334	$ 342,102