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LOANS AND ALLOWANCE FOR LOAN LOSSES - Troubled Debt Restructuring (Details) | 3 Months Ended |
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Mar. 31, 2019 USD ($) loan contract | Mar. 31, 2018 USD ($) loan contract | Dec. 31, 2018 USD ($)
Troubled Debt Restructurings [Abstract] |  |  |
Recorded investment in troubled debt restructurings | $ 6,700,000 |  | $ 6,800,000
Troubled debt restructuring reserve | 800,000 |  | 900,000
Troubled debt restructurings accruing interest under modified terms | 800,000 |  | 800,000
Troubled debt restructurings on non-accrual status | 5,900,000 |  | 6,000,000
Additional amounts committed to customers with loans classified as troubled debt restructurings | 0 |  | $ 0
TDR charge-offs | $ 0 |  |
Number of loans | contract | 0 | 0 |
Loans by class modified as troubled debt restructurings [Abstract] |  |  |
Number of loans | loan |  | 1 |
Pre-modification outstanding recorded investment |  | $ 100,000 |
Post-modification outstanding recorded investment |  | $ 100,000 |
Consumer Loans | Home equity lines and loans |  |  |
Troubled Debt Restructurings [Abstract] |  |  |
Extension of maturity date | 3 years |  |
Loans by class modified as troubled debt restructurings [Abstract] |  |  |
Number of loans | loan | 1 |  |
Pre-modification outstanding recorded investment | $ 137,000 |  |
Post-modification outstanding recorded investment | $ 137,000 |  |
Commercial and industrial | Commercial and Agricultural |  |  |
Loans by class modified as troubled debt restructurings [Abstract] |  |  |
Number of loans | loan | 1 | 1 |
Pre-modification outstanding recorded investment | $ 137,000 | $ 100,000 |
Post-modification outstanding recorded investment | $ 137,000 | $ 100,000 |

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