Consolidated Statements of Stockholders' Equity - USD ($) $ in Thousands	Total	Cumulative Effect, Period of Adoption, Adjustment	Preferred Stock	Common Stock	Surplus	Accumulated Other Comprehensive Income (Loss)	Undivided Profits	Undivided Profits Cumulative Effect, Period of Adoption, Adjustment	Landmark Bank	Landmark Bank Common Stock	Landmark Bank Surplus	Triumph	Triumph Common Stock	Triumph Surplus	Spirit	Spirit Common Stock	Spirit Surplus
Balance at Dec. 31, 2019	$ 2,988,924	$ (128,101)	$ 767	$ 1,136	$ 2,117,282	$ 20,891	$ 848,848	$ (128,101)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Comprehensive income	293,739					38,835	254,904
Stock issued for employee stock purchase plan	956			1	955
Stock-based compensation plans, net	9,110			3	9,107
Stock repurchases	(113,327)			(59)	(113,268)
Dividends on preferred stock	(52)						(52)
Dividends on common stock	(74,593)						(74,593)
Balance at Dec. 31, 2020	2,976,656		767	1,081	2,014,076	59,726	901,006
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Comprehensive income	200,885					(70,271)	271,156
Stock issued for employee stock purchase plan	1,170			1	1,169
Stock-based compensation plans, net	16,158			4	16,154
Stock issued for acquisition									$ 138,191	$ 45	$ 138,146	$ 127,899	$ 42	$ 127,857
Preferred stock retirement	(767)		(767)
Stock repurchases	(132,459)			(46)	(132,413)
Dividends on preferred stock	(47)						(47)
Dividends on common stock	(78,845)						(78,845)
Balance at Dec. 31, 2021	3,248,841		0	1,127	2,164,989	(10,545)	1,093,270
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Comprehensive income	(250,603)					(507,015)	256,412
Stock issued for employee stock purchase plan	1,151			1	1,150
Stock-based compensation plans, net	10,284			3	10,281
Stock issued for acquisition															$ 464,918	$ 183	$ 464,735
Stock repurchases	(111,133)			(44)	(111,089)
Dividends on common stock	(94,096)						(94,096)
Balance at Dec. 31, 2022	$ 3,269,362		$ 0	$ 1,270	$ 2,530,066	$ (517,560)	$ 1,255,586