LOANS AND ALLOWANCE FOR LOAN LOSSES - Summary of Loan Portfolio by Type of Loan (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Loans held for investment:
Total loans	$ 1,706,395	$ 1,659,535	$ 1,359,544
Deferred loan costs	601	560
Allowance for loan losses	(16,202)	(14,651)	(12,859)	$ (11,484)
Total net loans	1,690,794	1,645,444
Commercial and industrial
Loans held for investment:
Total loans	279,583	261,779	197,508
Allowance for loan losses	(2,056)	(1,751)	(1,581)	(1,592)
Construction and development
Loans held for investment:
Total loans	280,498	237,503	196,774
Allowance for loan losses	(2,378)	(1,920)	(1,724)	(1,161)
Commercial real estate
Loans held for investment:
Total loans	567,360	582,519	418,137
Allowance for loan losses	(6,853)	(6,025)	(4,585)	(3,264)
Farmland
Loans held for investment:
Total loans	57,476	67,845	59,023
Allowance for loan losses	(570)	(643)	(523)	(482)
1-4 family residential
Loans held for investment:
Total loans	412,166	393,067	374,371
Allowance for loan losses	(3,125)	(2,868)	(3,022)	(3,960)
Multi-family residential
Loans held for investment:
Total loans	37,379	38,386	36,574
Allowance for loan losses	(409)	(631)	(629)	(281)
Consumer
Loans held for investment:
Total loans	53,245	54,777	51,267
Allowance for loan losses	(602)	(565)	(602)	(585)
Agricultural
Loans held for investment:
Total loans	18,359	23,277	25,596
Allowance for loan losses	(197)	(238)	(187)	(153)
Overdrafts
Loans held for investment:
Total loans	329	382	294
Allowance for loan losses	$ (12)	$ (10)	$ (6)	$ (6)

Loans and leases receivable deferred costs.

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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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