LOANS AND ALLOWANCE FOR LOAN LOSSES - Summary of Loan Portfolio by Type of Loan (Details) - USD ($) $ in Thousands	Mar. 31, 2017	Dec. 31, 2016	Mar. 31, 2016	Dec. 31, 2015
Loans held for investment:
Total loans	$ 1,253,143	$ 1,245,135	$ 1,142,064
Less: Allowance for loan losses	11,928	11,484	9,665	$ 9,263
Total net loans	1,241,215	1,233,651
Unamortized loan costs, net of loan fees	1,055	1,210
Commercial and industrial
Loans held for investment:
Total loans	205,903	223,997	216,929
Less: Allowance for loan losses	1,763	1,592	1,385	1,878
Construction and development
Loans held for investment:
Total loans	152,760	129,366	92,831
Less: Allowance for loan losses	1,349	1,161	808	1,004
Commercial real estate
Loans held for investment:
Total loans	372,855	367,656	336,999
Less: Allowance for loan losses	3,387	3,264	2,251	2,106
Farmland
Loans held for investment:
Total loans	62,130	62,362	54,321
Less: Allowance for loan losses	472	482	350	400
1-4 family residential
Loans held for investment:
Total loans	360,873	362,952	334,423
Less: Allowance for loan losses	3,770	3,960	3,940	2,839
Multi-family residential
Loans held for investment:
Total loans	23,943	26,079	34,655
Less: Allowance for loan losses	228	281	338	325
Consumer
Loans held for investment:
Total loans	52,816	53,505	51,552
Less: Allowance for loan losses	798	585	446	562
Agricultural
Loans held for investment:
Total loans	21,473	18,901	19,808
Less: Allowance for loan losses	155	153	126	138
Overdrafts
Loans held for investment:
Total loans	390	317	546
Less: Allowance for loan losses	$ 6	$ 6	$ 21	$ 11

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 and after 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.

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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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Amount of deferred fees paid by borrowers and unamortized costs incurred to originate loans and leases, unamortized loan commitments and loan syndication fees, and premiums over or discounts from face amounts of loans that are being amortized into income as an adjustment to yield. Excludes amounts for loans and leases covered under loss sharing agreements.

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