CONSOLIDATED STATEMENTS OF CHANGES IN SHAREHOLDERS' EQUITY - USD ($) shares in Thousands, $ in Thousands	Total	Cumulative Effect, Period of Adoption, Adjustment	Cumulative Effect, Period of Adoption, Adjusted Balance	Series A Preferred Stock	Series B Preferred Stock	Common Stock	Preferred Stock	Preferred Stock Cumulative Effect, Period of Adoption, Adjusted Balance	Common Stock	Common Stock Cumulative Effect, Period of Adoption, Adjusted Balance	Common Stock Common Stock	Surplus	Surplus Cumulative Effect, Period of Adoption, Adjusted Balance	Surplus Common Stock	Retained Earnings	Retained Earnings Cumulative Effect, Period of Adoption, Adjustment	Retained Earnings Cumulative Effect, Period of Adoption, Adjusted Balance	Retained Earnings Series A Preferred Stock	Retained Earnings Series B Preferred Stock	Retained Earnings Common Stock	Accumulated Other Comprehensive Loss	Accumulated Other Comprehensive Loss Cumulative Effect, Period of Adoption, Adjusted Balance	Treasury Stock	Treasury Stock Cumulative Effect, Period of Adoption, Adjusted Balance
Beginning balance at Dec. 31, 2020	$ 4,592,120						$ 209,691		$ 141,746			$ 3,637,468			$ 611,158	$ (47,300)					$ (7,718)		$ (225)
Beginning balance (in shares) at Dec. 31, 2020									403,859
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	473,840														473,840
Other comprehensive loss,  net of tax	(10,214)																				(10,214)
Cash dividends declared:
Cash dividends declared on preferred stock				$ (7,188)	$ (5,500)													$ (7,188)	$ (5,500)
Cash dividends declared on common stock						$ (182,370)														$ (182,370)
Effect of stock incentive plan, net (in shares)									3,484
Effect of stock incentive plan, net	35,358								$ 1,238			39,931			(6,295)								484
Common stock issued (in shares)											15,709
Common stock issued in acquisition						211,134					$ 5,498			$ 205,636
Common stock repurchased (in shares)									(1,615)
Common stock repurchased	(23,114)																						(23,114)
Ending balance at Dec. 31, 2021	5,084,066						209,691		$ 148,482			3,883,035			883,645						(17,932)		(22,855)
Ending balance (in shares) at Dec. 31, 2021									421,437
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	568,851														568,851
Other comprehensive loss,  net of tax	(146,070)																				(146,070)
Cash dividends declared:
Cash dividends declared on preferred stock				(7,188)	(5,958)													(7,188)	(5,958)
Cash dividends declared on common stock						(215,513)														(215,513)
Effect of stock incentive plan, net (in shares)									1,089
Effect of stock incentive plan, net	18,302								$ 1			9,069			(5,392)								14,624
Common stock issued (in shares)											84,863
Common stock issued in acquisition						1,117,829					$ 29,702			$ 1,088,127
Common stock repurchased (in shares)									(1,015)
Common stock repurchased	(13,517)																						(13,517)
Ending balance at Dec. 31, 2022	6,400,802	$ 990	$ 6,401,792				209,691	$ 209,691	$ 178,185	$ 178,185		4,980,231	$ 4,980,231		1,218,445	$ 990	$ 1,219,435				(164,002)	$ (164,002)	(21,748)	$ (21,748)
Ending balance (in shares) at Dec. 31, 2022									506,374	506,374
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	498,511														498,511
Other comprehensive loss,  net of tax	17,546																				17,546
Cash dividends declared:
Cash dividends declared on preferred stock				$ (7,188)	$ (8,947)													$ (7,188)	$ (8,947)
Cash dividends declared on common stock						(225,779)														$ (225,779)
Effect of stock incentive plan, net (in shares)									1,309
Effect of stock incentive plan, net	23,798								$ 2			9,758			(4,011)								18,049
Common stock issued (in shares)											327
Common stock issued in acquisition						$ 3,750									(650)								4,400
Common stock repurchased (in shares)									(300)
Common stock repurchased	(2,092)																						(2,092)
Ending balance at Dec. 31, 2023	$ 6,701,391						$ 209,691		$ 178,187			$ 4,989,989			$ 1,471,371						$ (146,456)		$ (1,391)
Ending balance (in shares) at Dec. 31, 2023									507,710