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LOANS AND ALLOWANCE FOR LOAN LOSSES - Troubled Debt Restructuring (Details) | 3 Months Ended |
--- | --- | ---
Mar. 31, 2017 USD ($) | Mar. 31, 2017 USD ($) | Mar. 31, 2017 USD ($) loan | Mar. 31, 2016 USD ($) loan | Dec. 31, 2016 USD ($)
Troubled Debt Restructurings [Abstract] |  |  |  |  |
Recorded investment in troubled debt restructurings | $ 10,300,000 | $ 10,300,000 | $ 10,300,000 |  | $ 10,200,000
Troubled debt restructuring reserve | 900,000 | 900,000 | 900,000 |  | 900,000
Troubled debt restructurings accruing interest under modified terms | 5,900,000 | 5,900,000 | 5,900,000 |  | 5,800,000
Troubled debt restructurings on non-accrual status | 4,400,000 | 4,400,000 | 4,400,000 |  | 4,400,000
Additional amounts committed to customers with loans classified as troubled debt restructurings | 0 | $ 0 | $ 0 |  | $ 0
Reduction of interest rate duration |  |  |  | 3 years |
Additional amounts of interest and past due escrow payments capitalized |  |  |  | $ 4,000 |
Increase (decrease) in allowance for loan losses |  |  |  | 0 |
TDR charge-offs | 0 |  |  | $ 0 |
Number of Loans |  | 0 | 2 |  |
Loans by class modified as troubled debt restructurings [Abstract] |  |  |  |  |
Number of loans | loan |  |  | 1 | 1 |
Pre-modification outstanding recorded investment | 166,000 |  |  | $ 121,000 |
Post-modification outstanding recorded investment | 166,000 |  |  | $ 125,000 |
Recorded Investment | 2,145,000 |  |  |  |
Commercial mortgages |  |  |  |  |
Troubled Debt Restructurings [Abstract] |  |  |  |  |
Number of Loans | loan |  |  | 2 |  |
Loans by class modified as troubled debt restructurings [Abstract] |  |  |  |  |
Recorded Investment | 2,145,000 |  |  |  |
Commercial mortgages |  |  |  |  |
Loans by class modified as troubled debt restructurings [Abstract] |  |  |  |  |
Number of loans | loan |  |  | 1 |  |
Pre-modification outstanding recorded investment | 166,000 |  |  |  |
Post-modification outstanding recorded investment | $ 166,000 |  |  |  |
Residential mortgages |  |  |  |  |
Loans by class modified as troubled debt restructurings [Abstract] |  |  |  |  |
Number of loans | loan |  |  |  | 1 |
Pre-modification outstanding recorded investment |  |  |  | $ 121,000 |
Post-modification outstanding recorded investment |  |  |  | $ 125,000 |

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