Postretirement Benefits - Schedule of Net Periodic Benefit Cost (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2026	Mar. 31, 2025
Retirement Benefits [Abstract]
Service cost—benefits earned during the period	$ 6,837	$ 6,242
Interest cost on projected benefit obligation	9,611	9,025
Expected return on assets	(12,338)	(11,563)
Amortization of prior service cost (credit)	252	292
Recognition of actuarial gain (loss)	0	0
Net periodic benefit cost	$ 4,362	$ 3,996