CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (UNAUDITED) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2025	Sep. 30, 2024
Statement of Comprehensive Income [Abstract]
Net income	$ 182,853	$ 159,830	$ 495,955	$ 448,285
Other comprehensive income, net of tax
Change in unrealized holding gains on available-for-sale securities	6,105	20,227	18,144	21,014
Pension and other postretirement plans	(1,056)	(1,538)	(1,800)	(6,048)
Total other comprehensive income, net of tax	5,049	18,689	16,344	14,966
Comprehensive income	$ 187,902	$ 178,519	$ 512,299	$ 463,251