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DERIVATIVE FINANCIAL INSTRUMENTS - Narrative (Details) - USD ($) | 3 Months Ended |
--- | --- | ---
Mar. 31, 2021 | Mar. 31, 2020 | Dec. 31, 2020
Derivative [Line Items] |  |  |
Interest expense | $ 2,022,000 | $ 4,683,000 |
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 | 155,000 | $ 137,000 |
Designated as Hedging Instrument | Cash Flow Hedging | Interest Rate Swap | FHLB Advances |  |  |
Derivative [Line Items] |  |  |
Notional amount | $ 40,000,000 |  | $ 40,000,000

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