LOANS AND ALLOWANCE FOR LOAN LOSSES - Summary of Loan Portfolio by Type of Loan (Details) - USD ($) $ in Thousands	Jun. 30, 2017	Dec. 31, 2016	Jun. 30, 2016	Dec. 31, 2015
Loans held for investment:
Total loans	$ 1,296,843	$ 1,245,135	$ 1,185,161
Less: Allowance for loan losses	12,525	11,484	11,606	$ 9,263
Total net loans	1,284,318	1,233,651
Unamortized loan costs, net of loan fees	1,127	1,210
Commercial and industrial
Loans held for investment:
Total loans	217,497	223,997	218,397
Less: Allowance for loan losses	2,008	1,592	3,081	1,878
Construction and development
Loans held for investment:
Total loans	177,600	129,366	108,698
Less: Allowance for loan losses	1,554	1,161	1,043	1,004
Commercial real estate
Loans held for investment:
Total loans	378,722	367,656	347,432
Less: Allowance for loan losses	3,464	3,264	2,539	2,106
Farmland
Loans held for investment:
Total loans	63,839	62,362	66,174
Less: Allowance for loan losses	541	482	512	400
1-4 family residential
Loans held for investment:
Total loans	356,457	362,952	334,569
Less: Allowance for loan losses	3,726	3,960	3,329	2,839
Multi-family residential
Loans held for investment:
Total loans	28,833	26,079	36,860
Less: Allowance for loan losses	269	281	383	325
Consumer
Loans held for investment:
Total loans	51,677	53,505	53,027
Less: Allowance for loan losses	585	585	567	562
Agricultural
Loans held for investment:
Total loans	21,854	18,901	19,444
Less: Allowance for loan losses	371	153	131	138
Overdrafts
Loans held for investment:
Total loans	364	317	560
Less: Allowance for loan losses	$ 7	$ 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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