LOANS AND ALLOWANCE FOR LOAN LOSSES - Summary of Impaired Loans (Details) - USD ($) $ in Thousands	6 Months Ended	12 Months Ended
Jun. 30, 2019	Dec. 31, 2018
Unpaid Principal Balance [Abstract]
Unpaid Principal Balance, With no related allowance recorded	$ 7,445	$ 8,356
Unpaid Principal Balance, With related allowance recorded	8,257	3,000
Unpaid Principal Balance	15,702	11,356
Recorded Investment [Abstract]
Recorded Investment, With no related allowance recorded	7,445	8,356
Recorded Investment, With related allowance recorded	8,257	3,000
Recorded Investment, With related allowance recorded	15,702	11,356
Related Allowance [Abstract]
Related Allowance	1,147	493
Average Recorded Investment [Abstract]
Average Recorded Investment, With no related allowance recorded	3,685	8,202
Average Recorded Investment, With related allowance recorded	2,835	1,348
Average Recorded Investment, With related allowance recorded	6,520	9,550
Commercial and industrial
Unpaid Principal Balance [Abstract]
Unpaid Principal Balance, With no related allowance recorded	314	837
Unpaid Principal Balance, With related allowance recorded		185
Recorded Investment [Abstract]
Recorded Investment, With no related allowance recorded	314	837
Recorded Investment, With related allowance recorded		185
Related Allowance [Abstract]
Related Allowance		64
Average Recorded Investment [Abstract]
Average Recorded Investment, With no related allowance recorded	162	842
Average Recorded Investment, With related allowance recorded	61	300
Construction and development
Unpaid Principal Balance [Abstract]
Unpaid Principal Balance, With no related allowance recorded	1,237	720
Unpaid Principal Balance, With related allowance recorded		530
Recorded Investment [Abstract]
Recorded Investment, With no related allowance recorded	1,237	720
Recorded Investment, With related allowance recorded		530
Related Allowance [Abstract]
Related Allowance		4
Average Recorded Investment [Abstract]
Average Recorded Investment, With no related allowance recorded	623	518
Average Recorded Investment, With related allowance recorded		44
Commercial real estate
Unpaid Principal Balance [Abstract]
Unpaid Principal Balance, With no related allowance recorded	3,959	5,168
Unpaid Principal Balance, With related allowance recorded	8,070	1,985
Recorded Investment [Abstract]
Recorded Investment, With no related allowance recorded	3,959	5,168
Recorded Investment, With related allowance recorded	8,070	1,985
Related Allowance [Abstract]
Related Allowance	1,073	341
Average Recorded Investment [Abstract]
Average Recorded Investment, With no related allowance recorded	2,129	5,138
Average Recorded Investment, With related allowance recorded	2,645	677
Farmland
Unpaid Principal Balance [Abstract]
Unpaid Principal Balance, With related allowance recorded	133	140
Recorded Investment [Abstract]
Recorded Investment, With related allowance recorded	133	140
Related Allowance [Abstract]
Related Allowance	62	78
Average Recorded Investment [Abstract]
Average Recorded Investment, With no related allowance recorded		62
Average Recorded Investment, With related allowance recorded	69	147
1-4 family residential
Unpaid Principal Balance [Abstract]
Unpaid Principal Balance, With no related allowance recorded	1,703	1,223
Unpaid Principal Balance, With related allowance recorded	54	160
Recorded Investment [Abstract]
Recorded Investment, With no related allowance recorded	1,703	1,223
Recorded Investment, With related allowance recorded	54	160
Related Allowance [Abstract]
Related Allowance	12	6
Average Recorded Investment [Abstract]
Average Recorded Investment, With no related allowance recorded	640	1,132
Average Recorded Investment, With related allowance recorded	60	128
Multi-family residential
Average Recorded Investment [Abstract]
Average Recorded Investment, With no related allowance recorded		54
Agricultural
Unpaid Principal Balance [Abstract]
Unpaid Principal Balance, With no related allowance recorded	232	408
Recorded Investment [Abstract]
Recorded Investment, With no related allowance recorded	232	408
Average Recorded Investment [Abstract]
Average Recorded Investment, With no related allowance recorded	$ 131	456
Average Recorded Investment, With related allowance recorded		$ 52

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