CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Statement of Comprehensive Income [Abstract]
Net income	$ 559,335	$ 600,314	$ 446,061
Other comprehensive loss, net of tax
Change in unrealized holding gains on available-for-sale securities	18,920	7,079	27,784
Pension and other postretirement plans	(23,350)	(41,270)	(33,770)
Total other comprehensive loss, net of tax	(4,430)	(34,191)	(5,986)
Comprehensive income	$ 554,905	$ 566,123	$ 440,075