Postretirement Benefits - Pension Plan Cost (Income) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2025	Sep. 30, 2024
Retirement Benefits [Abstract]
Service cost for benefits earned	$ 8,866	$ 8,628	$ 26,590	$ 25,920
Interest cost on benefit obligation	14,688	13,195	44,039	39,503
Expected return on plan assets	(20,069)	(20,199)	(60,207)	(60,595)
Prior service cost amortization	422	413	1,266	1,199
Net actuarial gain amortization	(633)	(1,695)	(1,942)	(5,180)
Settlement gain	(62)	(59)	(539)	(1,338)
Pension plan cost (income)	$ 3,212	$ 283	$ 9,207	$ (491)
Defined Benefit Plan, Net Periodic Benefit Cost (Credit) Excluding Service Cost, Statement of Income or Comprehensive Income [Extensible Enumeration]			Other Nonoperating Income (Expense)