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DERIVATIVE FINANCIAL INSTRUMENTS - Narrative (Details) - USD ($) | 3 Months Ended | 12 Months Ended
--- | --- | ---
Mar. 31, 2020 | Mar. 31, 2019 | Dec. 31, 2019
Derivative [Line Items] |  |  |
Ineffectiveness included in net income | $ 0 |  |
Interest expense | 4,683,000 | $ 6,300,000 |
Unrealized loss to be reclassified as a reduction of interest expense | 0 |  |
Designated as Hedging Instrument | Cash Flow Hedging | Interest Rate Swap |  |  |
Derivative [Line Items] |  |  |
Notional amount | 5,000,000 |  | $ 5,000,000
Interest expense | 137,000 | $ 169,000 | $ 648,000
Designated as Hedging Instrument | Cash Flow Hedging | Interest Rate Swap | FHLB Advances |  |  |
Derivative [Line Items] |  |  |
Notional amount | $ 40,000,000 |  |

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