Consolidated Statements of Changes in Stockholders' Equity - USD ($) shares in Thousands, $ in Thousands	Total	Common Stock [Member]	Capital Surplus [Member]	Retained Earnings [Member]	Accumulated Other Comprehensive Income (Loss), Net [Member]
Balance at Dec. 31, 2022	$ 3,342,628	$ 309,513	$ 1,716,884	$ 2,088,413	$ (772,182)
Balance, Shares Issued at Dec. 31, 2022		92,947
Net income	392,602			392,602
Other comprehensive income	151,055				151,055
Comprehensive income	543,657
Cash dividends declared	(105,557)			(105,557)
Common stock activity, long-term incentive plans	19,118		18,972	146
Issuance of stock from dividend reinvestment and stock purchase plans	3,815		3,815
Balance at Dec. 31, 2023	3,803,661	$ 309,513	1,739,671	2,375,604	(621,127)
Balance, Shares Issued at Dec. 31, 2023		92,947
Net income	460,815			460,815
Other comprehensive income	15,035				15,035
Comprehensive income	475,850
Cash dividends declared	(131,946)			(131,946)
Common stock activity, long-term incentive plans	13,780		13,647	133
Issuance of stock from dividend reinvestment and stock purchase plans	4,120		4,120
Repurchase of common stock	(37,829)		(37,829)
Balance at Dec. 31, 2024	$ 4,127,636	$ 309,513	1,719,609	2,704,606	(606,092)
Balance, Shares Issued at Dec. 31, 2024	92,947	92,947
Net income	$ 486,073			486,073
Other comprehensive income	229,841				229,841
Comprehensive income	715,914
Cash dividends declared	(155,077)			(155,077)
Common stock activity, long-term incentive plans	16,177		16,143	34
Issuance of stock from dividend reinvestment and stock purchase plans	4,441		4,441
Repurchase of common stock	(248,974)		(248,974)
Balance at Dec. 31, 2025	$ 4,460,117	$ 309,513	$ 1,491,219	$ 3,035,636	$ (376,251)
Balance, Shares Issued at Dec. 31, 2025	92,947	92,947