Postretirement Benefits - Analysis of Impact on Other Comprehensive Income (Loss) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Defined Benefit Plan, Impact on Other Comprehensive Income
Balance at January 1	$ (2,727)	$ 1,570	$ (131,239)
Prior service cost (credit)	1,071	1,075	1,077
Net actuarial (gain) loss	(597)	(1,465)	12,677
Total amortization	474	(390)	13,754
Plan amendments	(1,212)	0	0
Experience gain (loss)	29,659	(3,907)	119,055
Balance at December 31	26,194	(2,727)	1,570
Other Benefits
Defined Benefit Plan, Impact on Other Comprehensive Income
Total amortization	$ (622)	$ (732)	$ 289