LOANS AND ALLOWANCE FOR LOAN LOSSES - Summary of Impaired Loans (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017
Unpaid Principal Balance [Abstract]
Unpaid Principal Balance, With no related allowance recorded	$ 8,356	$ 5,717
Unpaid Principal Balance, With related allowance recorded	3,000	623
Unpaid Principal Balance	11,356	6,340
Recorded Investment [Abstract]
Recorded Investment, With no related allowance recorded	8,356	5,717
Recorded Investment, With related allowance recorded	3,000	623
Recorded Investment	11,356	6,340
Related Allowance [Abstract]
Related Allowance	493	134
Average Recorded Investment [Abstract]
Average Recorded Investment, With no related allowance recorded	8,202	6,786
Average Recorded Investment, With related allowance recorded	1,348	1,953
Average Recorded Investment	9,550	8,739
Commercial and industrial
Unpaid Principal Balance [Abstract]
Unpaid Principal Balance, With no related allowance recorded	837	437
Unpaid Principal Balance, With related allowance recorded	185	26
Recorded Investment [Abstract]
Recorded Investment, With no related allowance recorded	837	437
Recorded Investment, With related allowance recorded	185	26
Related Allowance [Abstract]
Related Allowance	64	17
Average Recorded Investment [Abstract]
Average Recorded Investment, With no related allowance recorded	842	434
Average Recorded Investment, With related allowance recorded	300	315
Construction and development
Unpaid Principal Balance [Abstract]
Unpaid Principal Balance, With no related allowance recorded	720	0
Unpaid Principal Balance, With related allowance recorded	530	0
Recorded Investment [Abstract]
Recorded Investment, With no related allowance recorded	720	0
Recorded Investment, With related allowance recorded	530	0
Related Allowance [Abstract]
Related Allowance	4	0
Average Recorded Investment [Abstract]
Average Recorded Investment, With no related allowance recorded	518	311
Average Recorded Investment, With related allowance recorded	44	7
Commercial real estate
Unpaid Principal Balance [Abstract]
Unpaid Principal Balance, With no related allowance recorded	5,168	3,979
Unpaid Principal Balance, With related allowance recorded	1,985	279
Recorded Investment [Abstract]
Recorded Investment, With no related allowance recorded	5,168	3,979
Recorded Investment, With related allowance recorded	1,985	279
Related Allowance [Abstract]
Related Allowance	341	27
Average Recorded Investment [Abstract]
Average Recorded Investment, With no related allowance recorded	5,138	4,230
Average Recorded Investment, With related allowance recorded	677	505
Farmland
Unpaid Principal Balance [Abstract]
Unpaid Principal Balance, With no related allowance recorded	0	6
Unpaid Principal Balance, With related allowance recorded	140	157
Recorded Investment [Abstract]
Recorded Investment, With no related allowance recorded	0	6
Recorded Investment, With related allowance recorded	140	157
Related Allowance [Abstract]
Related Allowance	78	85
Average Recorded Investment [Abstract]
Average Recorded Investment, With no related allowance recorded	62	90
Average Recorded Investment, With related allowance recorded	147	131
1-4 family residential
Unpaid Principal Balance [Abstract]
Unpaid Principal Balance, With no related allowance recorded	1,223	681
Unpaid Principal Balance, With related allowance recorded	160	161
Recorded Investment [Abstract]
Recorded Investment, With no related allowance recorded	1,223	681
Recorded Investment, With related allowance recorded	160	161
Related Allowance [Abstract]
Related Allowance	6	5
Average Recorded Investment [Abstract]
Average Recorded Investment, With no related allowance recorded	1,132	1,096
Average Recorded Investment, With related allowance recorded	128	754
Multi-family residential
Unpaid Principal Balance [Abstract]
Unpaid Principal Balance, With no related allowance recorded	0	217
Unpaid Principal Balance, With related allowance recorded	0	0
Recorded Investment [Abstract]
Recorded Investment, With no related allowance recorded	0	217
Recorded Investment, With related allowance recorded	0	0
Related Allowance [Abstract]
Related Allowance	0	0
Average Recorded Investment [Abstract]
Average Recorded Investment, With no related allowance recorded	54	180
Average Recorded Investment, With related allowance recorded	0	19
Consumer
Unpaid Principal Balance [Abstract]
Unpaid Principal Balance, With no related allowance recorded	0	0
Unpaid Principal Balance, With related allowance recorded	0	0
Recorded Investment [Abstract]
Recorded Investment, With no related allowance recorded	0	0
Recorded Investment, With related allowance recorded	0	0
Related Allowance [Abstract]
Related Allowance	0	0
Average Recorded Investment [Abstract]
Average Recorded Investment, With no related allowance recorded	0	61
Average Recorded Investment, With related allowance recorded	0	42
Agricultural
Unpaid Principal Balance [Abstract]
Unpaid Principal Balance, With no related allowance recorded	408	397
Unpaid Principal Balance, With related allowance recorded	0	0
Recorded Investment [Abstract]
Recorded Investment, With no related allowance recorded	408	397
Recorded Investment, With related allowance recorded	0	0
Related Allowance [Abstract]
Related Allowance	0	0
Average Recorded Investment [Abstract]
Average Recorded Investment, With no related allowance recorded	456	384
Average Recorded Investment, With related allowance recorded	$ 52	$ 180

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