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ACQUISITIONS AND DISPOSITIONS - Narrative (Details) $ in Millions | 12 Months Ended |
--- | --- | ---
Dec. 31, 2024 USD ($) | Dec. 06, 2024 bankBranch
Business Acquisition [Line Items] |  |
Gain on branch sale | $ | $ 20.0 |
Sale | Old Second Bancorp, Inc. Branch Sale |  |
Business Acquisition [Line Items] |  |
Number of branches | bankBranch |  | 5

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