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DERIVATIVE FINANCIAL INSTRUMENTS AND HEDGING ACTIVITIES - Narrative (Details) | 3 Months Ended | 12 Months Ended
--- | --- | ---
Sep. 30, 2024 contracts | Jun. 30, 2023 contracts | Dec. 31, 2024 USD ($) | Dec. 31, 2023 USD ($) | Dec. 31, 2022 USD ($)
Derivative [Line Items] |  |  |  |  |
Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), Reclassification, before Tax |  |  | $ 22,042,000 | $ 24,544,000 | $ 3,638,000
Securities available for sale, at estimated fair value |  |  | 1,533,894,000 | 1,296,294,000 |
Gain (loss) on hedging activity |  |  | 3,500,000 | 6,500,000 |
Cash collateral received from counterparties under master netting agreements |  |  | 49,874,000 | 46,760,000 |
Derivatives designated as hedging instruments |  |  |  |  |
Derivative [Line Items] |  |  |  |  |
Interest Rate Swap Contacts Terminated, Number | contracts | 3 | 1 |  |  |
Interest Rate Swaps | Cash Flow Hedging |  |  |  |  |
Derivative [Line Items] |  |  |  |  |
Derivative, Notional Amount |  |  | 790,000,000.0 |  |
Interest Rate Swaps | Cash Flow Hedging | Derivatives designated as hedging instruments |  |  |  |  |
Derivative [Line Items] |  |  |  |  |
Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), Reclassification, before Tax |  |  | 22,042,000 | $ 24,544,000 | $ 3,638,000
Cash Flow Hedging |  |  |  |  |
Derivative [Line Items] |  |  |  |  |
Cash Flow Hedge Gain (Loss) estimated to be Reclassified within 12 Months |  |  | $ 7,500,000 |  |

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