LOANS AND ALLOWANCE FOR CREDIT LOSSES - Summary of Loan Portfolio by Type of Loan (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020	Mar. 31, 2020	Dec. 31, 2019
Loans held for investment:
Total loans	$ 1,912,367	$ 1,866,819
Deferred loan fees, net	(2,612)	(1,463)
Allowance for credit losses	(32,770)	(33,619)	$ (21,948)	$ (16,202)
Total net loans	1,876,985	1,831,737
Commercial and industrial
Loans held for investment:
Total loans	460,491	445,771
Allowance for credit losses	(3,529)	(4,033)	(2,924)	(2,056)
Construction and development
Loans held for investment:
Total loans	257,886	270,407
Allowance for credit losses	(4,198)	(4,735)	(2,578)	(2,378)
Commercial real estate
Loans held for investment:
Total loans	630,479	594,216
Allowance for credit losses	(16,109)	(15,780)	(9,761)	(6,853)
Farmland
Loans held for investment:
Total loans	76,867	78,508
Allowance for credit losses	(1,057)	(1,220)	(792)	(570)
1-4 family residential
Loans held for investment:
Total loans	389,542	389,096
Allowance for credit losses	(6,326)	(6,313)	(4,156)	(3,125)
Multi-family residential
Loans held for investment:
Total loans	32,090	21,701
Allowance for credit losses	(496)	(363)	(189)	(409)
Consumer
Loans held for investment:
Total loans	49,780	51,044
Allowance for credit losses	(843)	(929)	(693)	(602)
Agricultural
Loans held for investment:
Total loans	14,905	15,734
Allowance for credit losses	(208)	(239)	(281)	(197)
Overdrafts
Loans held for investment:
Total loans	327	342
Allowance for credit losses	$ (4)	$ (7)	$ (3)	$ (12)

Loans and leases receivable deferred fees net.

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Amount of allowance to cover probable credit losses on loans and leases. Includes carryover of or adjustments to the allowance for loan losses in connection with business combinations. Excludes allowance for loans and leases covered under loss sharing agreements.

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Amount before allowance of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes loans and leases covered under loss sharing agreements.

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Amount after allowance and deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Excludes loans and leases covered under loss sharing agreements and loans held for sale.

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