CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (UNAUDITED) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2025	Jun. 30, 2024	Jun. 30, 2025	Jun. 30, 2024
Statement of Comprehensive Income [Abstract]
Net income	$ 174,685	$ 163,903	$ 313,102	$ 288,455
Other comprehensive income (loss), net of tax
Change in unrealized holding gains on available-for-sale securities	6,261	1,541	12,039	787
Pension and other postretirement plans	(183)	(3,434)	(744)	(4,510)
Total other comprehensive income (loss), net of tax	6,078	(1,893)	11,295	(3,723)
Comprehensive income	$ 180,763	$ 162,010	$ 324,397	$ 284,732