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LOANS AND ALLOWANCE FOR LOAN LOSSES - Troubled Debt Restructuring (Details) | 3 Months Ended |
--- | --- | ---
Mar. 31, 2020 USD ($) loan contract | Mar. 31, 2019 USD ($) loan contract | Dec. 31, 2019 USD ($)
Troubled Debt Restructurings [Abstract] |  |  |
Recorded investment in troubled debt restructurings | $ 8,700,000 |  | $ 9,000,000
Troubled debt restructuring reserve | 2,300,000 |  | 2,300,000
Troubled debt restructurings accruing interest under modified terms | 800,000 |  | 900,000
Troubled debt restructurings on non-accrual status | 7,900,000 |  | 8,100,000
Additional amounts committed to customers with loans classified as troubled debt restructurings | 0 |  | $ 0
TDR charge-offs | $ 0 | $ 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 |  | $ 137,000 |
Post-modification outstanding recorded investment |  | $ 137,000 |
Commercial and Consumer Loans |  |  |
Loans by class modified as troubled debt restructurings [Abstract] |  |  |
Number of loans | loan | 444 |  |
Post-modification outstanding recorded investment | $ 56,600,000 |  |
Consumer Loans | Home equity lines and loans |  |  |
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 |
Interest Rate Below Market Reduction | Consumer Loans | Home equity lines and loans |  |  |
Loans by class modified as troubled debt restructurings [Abstract] |  |  |
Number of loans | loan |  | 1 |
Principal Forgiveness |  |  |
Troubled Debt Restructurings [Abstract] |  |  |
Extension period |  | 3 years |

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