Consolidated Statements of Stockholders' Equity - USD ($) $ in Thousands	Total	Common Stock	Surplus	Accumulated Other Comprehensive Income (Loss)	Undivided Profits
Beginning balance at Dec. 31, 2022	$ 3,269,362	$ 1,270	$ 2,530,066	$ (517,560)	$ 1,255,586
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Comprehensive income	288,242			113,185	175,057
Stock issued for employee stock purchase plan	833	0	833
Stock-based compensation plans, net	9,335	5	9,330
Stock repurchases	(40,322)	(23)	(40,299)
Dividends on common stock	(100,962)				(100,962)
Ending balance at Dec. 31, 2023	3,426,488	1,252	2,499,930	(404,375)	1,329,681
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Comprehensive income	196,158			43,465	152,693
Stock issued for employee stock purchase plan	970	0	970
Stock-based compensation plans, net	10,695	5	10,690
Dividends on common stock	(105,439)				(105,439)
Ending balance at Dec. 31, 2024	3,528,872	1,257	2,511,590	(360,910)	1,376,935
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Comprehensive income	(329,773)			67,780	(397,553)
Stock issued for employee stock purchase plan	836	0	836
Stock-based compensation plans, net	7,239	4	7,235
Issuance of common stock	327,107	187	326,920
Dividends on common stock	(115,041)				(115,041)
Ending balance at Dec. 31, 2025	$ 3,419,240	$ 1,448	$ 2,846,581	$ (293,130)	$ 864,341