ACQUISITIONS - Fair Value (Details) - USD ($) $ in Thousands		12 Months Ended
	May 15, 2020	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Liabilities assumed
Deposits	$ 63,100	$ 379,200
Goodwill	4,500	30,588	$ 24,191	$ 19,686
Total loans held for investment		1,954,168	1,534,185
Cash, Securities and Other
Liabilities assumed
Total loans held for investment		295,948	357,020
Construction and Development
Liabilities assumed
Total loans held for investment		178,716	131,111
1-4 Family Residential
Liabilities assumed
Total loans held for investment		580,872	455,038
Non-Owner Occupied CRE
Liabilities assumed
Total loans held for investment		482,622	281,943
Owner Occupied CRE
Liabilities assumed
Total loans held for investment		212,426	163,042
Commercial. and Industrial.
Liabilities assumed
Total loans held for investment		203,584	146,031
PPP Loans
Liabilities assumed
Total loans held for investment		46,800	142,900
Simmons Bank
Business Acquisition [Line Items]
Cash consideration	61,599
Total fair value of consideration transferred	61,599
Assets acquired
Cash and cash equivalents	283
Total loans	120,642
Loans, net	119,552
Core deposit intangible	53
Accrued income and other assets	382
Total assets acquired	120,270
Liabilities assumed
Deposits	63,080
Accrued expenses and other liabilities	96
Total liabilities assumed	63,176
Net assets acquired	57,094
Goodwill	4,505
Total loans held for investment		356,700	127,200
Acquisition cost			$ 700
Simmons Bank | Cash, Securities and Other
Assets acquired
Total loans	13,457
Simmons Bank | Construction and Development
Assets acquired
Total loans	40,407
Simmons Bank | 1-4 Family Residential
Assets acquired
Total loans	7,252
Simmons Bank | Non-Owner Occupied CRE
Assets acquired
Total loans	545
Simmons Bank | Owner Occupied CRE
Assets acquired
Total loans	321
Simmons Bank | Commercial. and Industrial.
Assets acquired
Total loans	58,660
Simmons Bank | PPP Loans
Liabilities assumed
Total loans held for investment	$ 12,900
Teton Financial Services
Business Acquisition [Line Items]
Cash consideration		11,501
Common stock issued		39,818
Total fair value of consideration transferred		51,319
Assets acquired
Cash and cash equivalents		132,498
Available-for-sale securities, at fair value		18,218
Coorespondant bank stock, at cost		928
Mortgage loans held for sale		840
Total loans		256,257
Acquisition fair value adjustments		(3,982)
Loans, net		252,275
Premises and equipment		17,758
Accrued interest receivable		923
Accounts receivable		95
Other receivable		520
Core deposit intangible		1,264
Other assets		66
Assets held for sale		115
Total assets acquired		425,500
Liabilities assumed
Deposits		379,227
Accrued interest payable		26
Other liabilities		1,283
Deferred tax liabilities, net		42
Total liabilities assumed		380,578
Net assets acquired		44,922
Goodwill		6,397
Acquisition cost		4,100
Teton Financial Services | Cash, Securities and Other
Assets acquired
Total loans		20,080
Teton Financial Services | Construction and Development
Assets acquired
Total loans		33,977
Teton Financial Services | 1-4 Family Residential
Assets acquired
Total loans		70,348
Teton Financial Services | Non-Owner Occupied CRE
Assets acquired
Total loans		43,162
Teton Financial Services | Owner Occupied CRE
Assets acquired
Total loans		33,000
Teton Financial Services | Commercial. and Industrial.
Assets acquired
Total loans		55,690
Teton Financial Services | PPP Loans
Liabilities assumed
Total loans held for investment		$ 6,700
Core deposit
Liabilities assumed
Estimated life	10 years	10 years