Consolidated Statements of Changes in Shareholders' Equity - USD ($) $ in Thousands	Total	Preferred Stock [Member]	Common Stock	Capital Surplus [Member]	Retained Earnings [Member]	Treasury Stock [Member]	Accumulated Other Comprehensive Gain (Loss) [Member]	Deferred Benefits for Directors [Member]
Beginning Balance at Dec. 31, 2020	$ 2,756,737	$ 144,484	$ 141,834	$ 1,634,815	$ 831,688	$ (25,949)	$ 31,359	$ (1,494)
Beginning Balance, shares at Dec. 31, 2020			67,254,706
Net Income (Loss)	242,260				242,260
Other comprehensive income (loss)	(36,479)						(36,479)
Comprehensive income (loss)	205,781
Common dividends declared	(85,667)				(85,667)
Preferred dividends declared	(10,125)				(10,125)
Stock issued for dividend reinvestment					(391)	391
Stock issued for dividend reinvestment, shares			11,720
Treasury shares acquired	(182,977)			194		(183,171)
Treasury shares acquired, shares			(5,218,275)
Stock options exercised	3,096			(1,388)		4,484
Stock options exercised, shares			130,273
Restricted stock granted				(4,486)		4,486
Restricted stock granted, shares			128,821
Stock compensation expense	6,475			6,475
Deferred benefits for directors-net	(154)			32				(186)
Ending Balance at Dec. 31, 2021	2,693,166	144,484	$ 141,834	1,635,642	977,765	(199,759)	(5,120)	(1,680)
Ending Balance, shares at Dec. 31, 2021			62,307,245
Net Income (Loss)	192,113				192,113
Other comprehensive income (loss)	(257,296)						(257,296)
Comprehensive income (loss)	(65,183)
Common dividends declared	(81,286)				(81,286)
Preferred dividends declared	(10,125)				(10,125)
Stock issued for dividend reinvestment					(792)	792
Stock issued for dividend reinvestment, shares			23,478
Treasury shares acquired	(119,097)					(119,097)
Treasury shares acquired, shares			(3,407,016)
Stock options exercised	3,050			(529)		3,579
Stock options exercised, shares			111,050
Restricted stock granted				(5,521)		5,521
Restricted stock granted, shares			164,206
Stock compensation expense	6,246			6,246
Deferred benefits for directors-net	(109)			39				(148)
Ending Balance at Dec. 31, 2022	2,426,662	144,484	$ 141,834	1,635,877	1,077,675	(308,964)	(262,416)	(1,828)
Ending Balance, shares at Dec. 31, 2022			59,198,963
Net Income (Loss)	159,032				159,032
Other comprehensive income (loss)	35,723						35,723
Comprehensive income (loss)	194,755
Common dividends declared	(82,906)				(82,906)
Preferred dividends declared	(10,125)				(10,125)
Stock issued for dividend reinvestment					(1,090)	1,090
Stock issued for dividend reinvestment, shares			29,871
Treasury shares acquired	(3,745)					(3,745)
Treasury shares acquired, shares			(162,432)
Stock options exercised	$ 237			(127)		364
Stock options exercised, shares	27,385		10,755
Restricted stock granted				(8,260)		8,260
Restricted stock granted, shares			299,278
Stock compensation expense	$ 8,324			8,324
Deferred benefits for directors-net	(140)			45				(185)
Ending Balance at Dec. 31, 2023	$ 2,533,062	$ 144,484	$ 141,834	$ 1,635,859	$ 1,142,586	$ (302,995)	$ (226,693)	$ (2,013)
Ending Balance, shares at Dec. 31, 2023			59,376,435