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LOANS AND ALLOWANCE FOR LOAN LOSSES - Summary of Impaired Loans (Details) - USD ($) $ in Thousands | 9 Months Ended | 12 Months Ended
--- | --- | ---
Sep. 30, 2017 | Sep. 30, 2016 | Dec. 31, 2016
Unpaid Principal Balance [Abstract] |  |  |
Unpaid Principal Balance, With no related allowance recorded | $ 5,047 |  | $ 5,062
Unpaid Principal Balance, With related allowance recorded | 1,633 |  | 1,256
Unpaid Principal Balance | 6,680 |  | 6,318
Recorded Investment [Abstract] |  |  |
Recorded Investment, With no related allowance recorded | 5,047 |  | 5,062
Recorded Investment, With related allowance recorded | 1,633 |  | 1,256
Recorded Investment | 6,680 |  | 6,318
Related Allowance [Abstract] |  |  |
Related Allowance | 520 |  | 253
Average Recorded Investment [Abstract] |  |  |
Average Recorded Investment, With no related allowance recorded | 7,180 |  | 3,695
Average Recorded Investment, With related allowance recorded | 2,248 |  | 4,118
Average Recorded Investment | 9,428 |  | 7,813
Interest income | 0 | $ 0 |
Cash-based interest income | 0 | $ 0 |
Commercial and industrial |  |  |
Unpaid Principal Balance [Abstract] |  |  |
Unpaid Principal Balance, With no related allowance recorded | 325 |  | 28
Unpaid Principal Balance, With related allowance recorded | 29 |  | 203
Recorded Investment [Abstract] |  |  |
Recorded Investment, With no related allowance recorded | 325 |  | 28
Recorded Investment, With related allowance recorded | 29 |  | 203
Related Allowance [Abstract] |  |  |
Related Allowance | 19 |  | 64
Average Recorded Investment [Abstract] |  |  |
Average Recorded Investment, With no related allowance recorded | 381 |  | 809
Average Recorded Investment, With related allowance recorded | 411 |  | 3,153
Construction and development |  |  |
Unpaid Principal Balance [Abstract] |  |  |
Unpaid Principal Balance, With no related allowance recorded | 0 |  | 1,825
Unpaid Principal Balance, With related allowance recorded | 0 |  |
Recorded Investment [Abstract] |  |  |
Recorded Investment, With no related allowance recorded | 0 |  | 1,825
Recorded Investment, With related allowance recorded | 0 |  |
Related Allowance [Abstract] |  |  |
Related Allowance | 0 |  |
Average Recorded Investment [Abstract] |  |  |
Average Recorded Investment, With no related allowance recorded | 415 |  | 172
Average Recorded Investment, With related allowance recorded | 10 |  |
Commercial real estate |  |  |
Unpaid Principal Balance [Abstract] |  |  |
Unpaid Principal Balance, With no related allowance recorded | 3,746 |  | 1,196
Unpaid Principal Balance, With related allowance recorded | 283 |  |
Recorded Investment [Abstract] |  |  |
Recorded Investment, With no related allowance recorded | 3,746 |  | 1,196
Recorded Investment, With related allowance recorded | 283 |  |
Related Allowance [Abstract] |  |  |
Related Allowance | 31 |  |
Average Recorded Investment [Abstract] |  |  |
Average Recorded Investment, With no related allowance recorded | 4,363 |  | 871
Average Recorded Investment, With related allowance recorded | 580 |  |
Farmland |  |  |
Unpaid Principal Balance [Abstract] |  |  |
Unpaid Principal Balance, With no related allowance recorded | 120 |  | 89
Unpaid Principal Balance, With related allowance recorded | 156 |  | 169
Recorded Investment [Abstract] |  |  |
Recorded Investment, With no related allowance recorded | 120 |  | 89
Recorded Investment, With related allowance recorded | 156 |  | 169
Related Allowance [Abstract] |  |  |
Related Allowance | 85 |  | 47
Average Recorded Investment [Abstract] |  |  |
Average Recorded Investment, With no related allowance recorded | 106 |  | 109
Average Recorded Investment, With related allowance recorded | 122 |  | 169
1-4 family residential |  |  |
Unpaid Principal Balance [Abstract] |  |  |
Unpaid Principal Balance, With no related allowance recorded | 231 |  | 1,799
Unpaid Principal Balance, With related allowance recorded | 866 |  | 789
Recorded Investment [Abstract] |  |  |
Recorded Investment, With no related allowance recorded | 231 |  | 1,799
Recorded Investment, With related allowance recorded | 866 |  | 789
Related Allowance [Abstract] |  |  |
Related Allowance | 145 |  | 108
Average Recorded Investment [Abstract] |  |  |
Average Recorded Investment, With no related allowance recorded | 1,288 |  | 1,575
Average Recorded Investment, With related allowance recorded | 867 |  | 639
Multi-family residential |  |  |
Unpaid Principal Balance [Abstract] |  |  |
Unpaid Principal Balance, With no related allowance recorded | 228 |  | 5
Unpaid Principal Balance, With related allowance recorded | 0 |  |
Recorded Investment [Abstract] |  |  |
Recorded Investment, With no related allowance recorded | 228 |  | 5
Recorded Investment, With related allowance recorded | 0 |  |
Related Allowance [Abstract] |  |  |
Related Allowance | 0 |  |
Average Recorded Investment [Abstract] |  |  |
Average Recorded Investment, With no related allowance recorded | 166 |  | 2
Average Recorded Investment, With related allowance recorded | 26 |  |
Consumer |  |  |
Unpaid Principal Balance [Abstract] |  |  |
Unpaid Principal Balance, With no related allowance recorded | 0 |  | 105
Unpaid Principal Balance, With related allowance recorded | 0 |  | 95
Recorded Investment [Abstract] |  |  |
Recorded Investment, With no related allowance recorded | 0 |  | 105
Recorded Investment, With related allowance recorded | 0 |  | 95
Related Allowance [Abstract] |  |  |
Related Allowance | 0 |  | 34
Average Recorded Investment [Abstract] |  |  |
Average Recorded Investment, With no related allowance recorded | 81 |  | 89
Average Recorded Investment, With related allowance recorded | 56 |  | 155
Agricultural |  |  |
Unpaid Principal Balance [Abstract] |  |  |
Unpaid Principal Balance, With no related allowance recorded | 397 |  | 15
Unpaid Principal Balance, With related allowance recorded | 299 |  | 0
Recorded Investment [Abstract] |  |  |
Recorded Investment, With no related allowance recorded | 397 |  | 15
Recorded Investment, With related allowance recorded | 299 |  | 0
Related Allowance [Abstract] |  |  |
Related Allowance | 240 |  | 0
Average Recorded Investment [Abstract] |  |  |
Average Recorded Investment, With no related allowance recorded | 380 |  | 68
Average Recorded Investment, With related allowance recorded | $ 176 |  | $ 2

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