LOANS AND ALLOWANCE FOR LOAN LOSSES - Summary of Loan Portfolio by Type of Loan (Details) - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018	Sep. 30, 2018	Dec. 31, 2017
Loans held for investment:
Total loans	$ 1,736,439	$ 1,659,535	$ 1,651,863
Deferred loan costs	550	560
Allowance for loan losses	(16,394)	(14,651)	(14,441)	$ (12,859)
Total net loans	1,720,595	1,645,444
Commercial and industrial
Loans held for investment:
Total loans	299,714	261,779	248,758
Allowance for loan losses	(2,057)	(1,751)	(1,707)	(1,581)
Construction and development
Loans held for investment:
Total loans	256,459	237,503	229,307
Allowance for loan losses	(2,135)	(1,920)	(1,843)	(1,724)
Commercial real estate
Loans held for investment:
Total loans	581,742	582,519	599,153
Allowance for loan losses	(6,889)	(6,025)	(5,882)	(4,585)
Farmland
Loans held for investment:
Total loans	61,073	67,845	65,209
Allowance for loan losses	(594)	(643)	(623)	(523)
1-4 family residential
Loans held for investment:
Total loans	406,880	393,067	392,456
Allowance for loan losses	(3,077)	(2,868)	(2,891)	(3,022)
Multi-family residential
Loans held for investment:
Total loans	58,198	38,386	38,523
Allowance for loan losses	(830)	(631)	(670)	(629)
Consumer
Loans held for investment:
Total loans	53,315	54,777	53,947
Allowance for loan losses	(600)	(565)	(569)	(602)
Agricultural
Loans held for investment:
Total loans	18,728	23,277	24,184
Allowance for loan losses	(201)	(238)	(247)	(187)
Overdrafts
Loans held for investment:
Total loans	330	382	326
Allowance for loan losses	$ (11)	$ (10)	$ (9)	$ (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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