Acquisitions - Assets Acquired and Liabilities Assumed (Details) - USD ($) $ in Thousands	Oct. 31, 2019	Apr. 12, 2019	Dec. 31, 2021	Oct. 08, 2021	Dec. 31, 2020	Dec. 31, 2019	Oct. 30, 2019	Apr. 11, 2019
Liabilities Assumed
Goodwill			$ 1,146,007		$ 1,075,305
Landmark Community Bank
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Assets [Abstract]
Cash and due from banks	$ 27,591						$ 27,591
Due from banks - time	100						100
Investment securities	114,528						114,793
Loans acquired	789,318			$ 789,300			785,551
Allowance for loan losses	(2,359)						(5,980)
Premises and equipment	5,441						9,540
Bank owned life insurance	21,287						21,287
Other assets	8,428						13,036
Total assets acquired	968,493			968,500			966,006
Liabilities Assumed
Non-interest bearing transaction accounts	110,393						110,393
Interest bearing transaction accounts and savings deposits	425,777						425,777
Time deposits	266,501						266,835
Total deposits	802,671			802,700			803,005
Other borrowings	47,023						47,023
Accrued interest and other liabilities	5,337						8,459
Total liabilities assumed	855,031						858,487
Total equity assumed	0						107,519
Total liabilities and equity assumed	855,031						966,006
Net assets acquired	113,462
Purchase price	145,195
Goodwill	31,733			31,700
Landmark Community Bank | Core deposit intangible
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Assets [Abstract]
Core deposit intangible	4,159						88
Landmark Community Bank | Fair Value Adjustments
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Assets [Abstract]
Cash and due from banks	0
Due from banks - time	0
Investment securities	(265)
Loans acquired	3,767
Allowance for loan losses	3,621
Premises and equipment	(4,099)
Bank owned life insurance	0
Other assets	(4,608)
Total assets acquired	2,487
Liabilities Assumed
Non-interest bearing transaction accounts	0
Interest bearing transaction accounts and savings deposits	0
Time deposits	(334)
Total deposits	(334)
Other borrowings	0
Accrued interest and other liabilities	(3,122)
Total liabilities assumed	(3,456)
Total equity assumed	(107,519)
Total liabilities and equity assumed	(110,975)
Landmark Community Bank | Fair Value Adjustments | Core deposit intangible
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Assets [Abstract]
Core deposit intangible	4,071
Triumph Bancshares, Inc.
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Assets [Abstract]
Cash and due from banks	7,484						7,484
Due from banks - time	495						495
Investment securities	129,465						130,571
Loans acquired	700,440			700,400			702,460
Allowance for loan losses	(11,092)						(12,617)
Premises and equipment	3,258						2,774
Goodwill	0						1,550
Other assets	13,015						12,806
Total assets acquired	848,201			848,200			845,523
Liabilities Assumed
Non-interest bearing transaction accounts	115,729						115,729
Interest bearing transaction accounts and savings deposits	383,434						383,434
Time deposits	220,571						219,477
Total deposits	719,734			719,700			718,640
Other borrowings	2,854						2,854
Subordinated debentures	30,700						30,700
Accrued interest and other liabilities	3,337						2,882
Total liabilities assumed	756,625						755,076
Total equity assumed	0						90,446
Total liabilities and equity assumed	756,625						845,522
Net assets acquired	91,576
Purchase price	130,544
Goodwill	38,968			$ 39,000
Triumph Bancshares, Inc. | Core deposit intangible
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Assets [Abstract]
Core deposit intangible	5,136						0
Triumph Bancshares, Inc. | Fair Value Adjustments
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Assets [Abstract]
Cash and due from banks	0
Due from banks - time	0
Investment securities	(1,106)
Loans acquired	(2,020)
Allowance for loan losses	1,525
Premises and equipment	484
Goodwill	(1,550)
Other assets	209
Total assets acquired	2,678
Liabilities Assumed
Non-interest bearing transaction accounts	0
Interest bearing transaction accounts and savings deposits	0
Time deposits	1,094
Total deposits	1,094
Other borrowings	0
Subordinated debentures	0
Accrued interest and other liabilities	455
Total liabilities assumed	1,549
Total equity assumed	(90,446)
Total liabilities and equity assumed	(88,897)
Triumph Bancshares, Inc. | Fair Value Adjustments | Core deposit intangible
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Assets [Abstract]
Core deposit intangible	5,136
Landrum Company
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Assets [Abstract]
Cash and due from banks	215,285						215,285
Due from banks - time	248						248
Investment securities	1,025,983						1,021,755
Loans acquired	2,005,486						2,049,137
Allowance for loan losses	0						(22,736)
Foreclosed assets	190						373
Premises and equipment	82,659						63,878
Bank owned life insurance	19,206						19,206
Goodwill	0						407
Other assets	20,634						33,924
Total assets acquired	3,399,152						3,381,889
Liabilities Assumed
Non-interest bearing transaction accounts	716,675						716,675
Interest bearing transaction accounts and savings deposits	1,465,429						1,465,429
Time deposits	867,496						867,197
Total deposits	3,049,600						3,049,301
Other borrowings	10,055						10,055
Subordinated debentures	33,917						34,794
Accrued interest and other liabilities	40,926						31,057
Total liabilities assumed	3,134,498						3,125,207
Total equity assumed	0						256,682
Total liabilities and equity assumed	3,134,498						3,381,889
Net assets acquired	264,654
Purchase price	415,779
Goodwill	151,125					$ 131,300
Landrum Company | Core deposit intangible
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Assets [Abstract]
Core deposit intangible	24,345						0
Landrum Company | Other intangibles
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Assets [Abstract]
Core deposit intangible	5,116						$ 412
Landrum Company | Fair Value Adjustments
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Assets [Abstract]
Cash and due from banks	0
Due from banks - time	0
Investment securities	4,228
Loans acquired	(43,651)
Allowance for loan losses	22,736
Foreclosed assets	(183)
Premises and equipment	18,781
Bank owned life insurance	0
Goodwill	(407)
Other assets	(13,290)
Total assets acquired	17,263
Liabilities Assumed
Non-interest bearing transaction accounts	0
Interest bearing transaction accounts and savings deposits	0
Time deposits	299
Total deposits	299
Other borrowings	0
Subordinated debentures	(877)
Accrued interest and other liabilities	9,869
Total liabilities assumed	9,291
Total equity assumed	(256,682)
Total liabilities and equity assumed	(247,391)
Landrum Company | Fair Value Adjustments | Core deposit intangible
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Assets [Abstract]
Core deposit intangible	24,345
Landrum Company | Fair Value Adjustments | Other intangibles
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Assets [Abstract]
Core deposit intangible	$ 4,704
Reliance Bancshares, Inc.
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Assets [Abstract]
Cash and due from banks		$ 25,693						$ 25,693
Due from banks - time		502						502
Investment securities		286,110						287,983
Loans acquired		1,096,870						1,138,527
Allowance for loan losses		0						(10,808)
Foreclosed assets		5,912						11,092
Premises and equipment		29,451						32,452
Bank owned life insurance		39,348						39,348
Core deposit intangible		18,350						0
Other assets		32,076						25,165
Total assets acquired		1,534,312						1,549,954
Liabilities Assumed
Non-interest bearing transaction accounts		108,812						108,845
Interest bearing transaction accounts and savings deposits		639,798						639,798
Time deposits		476,657						478,415
Total deposits		1,225,267						1,227,058
Total deposits		14,146						14,146
Other borrowings		157,400						162,900
Accrued interest and other liabilities		8,453						8,185
Total liabilities assumed		1,405,266						1,412,289
Total equity assumed		0						137,665
Total liabilities and equity assumed		1,405,266						$ 1,549,954
Net assets acquired		129,046
Purchase price		207,539
Goodwill		78,493				$ 78,500
Reliance Bancshares, Inc. | Fair Value Adjustments
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Assets [Abstract]
Cash and due from banks		0
Due from banks - time		0
Investment securities		(1,873)
Loans acquired		(41,657)
Allowance for loan losses		10,808
Foreclosed assets		(5,180)
Premises and equipment		(3,001)
Bank owned life insurance		0
Core deposit intangible		18,350
Other assets		6,911
Total assets acquired		(15,642)
Liabilities Assumed
Non-interest bearing transaction accounts		(33)
Interest bearing transaction accounts and savings deposits		0
Time deposits		(1,758)
Total deposits		(1,791)
Total deposits		0
Other borrowings		(5,500)
Accrued interest and other liabilities		268
Total liabilities assumed		(7,023)
Total equity assumed		(137,665)
Total liabilities and equity assumed		$ (144,688)