LOANS AND ALLOWANCE FOR LOAN LOSSES - Summary of Loan Portfolio by Type of Loan (Details) - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018	Jun. 30, 2018	Dec. 31, 2017
Loans held for investment:
Total loans	$ 1,693,847	$ 1,659,535	$ 1,593,474
Deferred loan costs	601	560
Allowance for loan losses	(15,743)	(14,651)	(13,890)	$ (12,859)
Total net loans	1,678,705	1,645,444
Commercial and industrial
Loans held for investment:
Total loans	286,190	261,779	234,396
Allowance for loan losses	(2,011)	(1,751)	(1,742)	(1,581)
Construction and development
Loans held for investment:
Total loans	231,167	237,503	211,745
Allowance for loan losses	(1,875)	(1,920)	(1,642)	(1,724)
Commercial real estate
Loans held for investment:
Total loans	592,945	582,519	570,448
Allowance for loan losses	(6,773)	(6,025)	(5,556)	(4,585)
Farmland
Loans held for investment:
Total loans	71,009	67,845	68,272
Allowance for loan losses	(658)	(643)	(648)	(523)
1-4 family residential
Loans held for investment:
Total loans	391,789	393,067	392,940
Allowance for loan losses	(2,926)	(2,868)	(2,832)	(3,022)
Multi-family residential
Loans held for investment:
Total loans	44,699	38,386	39,023
Allowance for loan losses	(676)	(631)	(698)	(629)
Consumer
Loans held for investment:
Total loans	56,099	54,777	52,949
Allowance for loan losses	(204)	(565)	(522)	(602)
Agricultural
Loans held for investment:
Total loans	19,721	23,277	23,362
Allowance for loan losses	(613)	(238)	(238)	(187)
Overdrafts
Loans held for investment:
Total loans	228	382	339
Allowance for loan losses	$ (7)	$ (10)	$ (12)	$ (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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