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INVESTMENT SECURITIES - Narrative (Details) - USD ($) $ in Millions | 3 Months Ended | 9 Months Ended |
--- | --- | --- | ---
Sep. 30, 2024 | Sep. 30, 2023 | Sep. 30, 2024 | Sep. 30, 2023 | Dec. 31, 2023
Debt Securities, Available-for-sale [Line Items] |  |  |  |  |
Trading gains (losses) recorded in servicing income | $ 1.1 | $ (0.9) | $ 0.2 | $ (1.4) |
Tax exempt interest income on available-for-sale securities | $ 2.8 | $ 2.8 | $ 8.4 | $ 8.4 |
Mortgage Backed Securities and Collateralized Mortgage Obligations |  |  |  |  |
Debt Securities, Available-for-sale [Line Items] |  |  |  |  |
Weighted average yield | 3.12% |  | 3.12% |  | 3.21%
US Treasury Notes Securities | Not Designated as Hedging Instrument, Economic Hedge |  |  |  |  |
Debt Securities, Available-for-sale [Line Items] |  |  |  |  |
Trading securities | $ 38.0 |  | $ 38.0 |  | $ 25.0

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