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INVESTMENT SECURITIES - Narrative (Details) - USD ($) $ in Millions | 12 Months Ended
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Dec. 31, 2022 | Dec. 31, 2021 | Dec. 31, 2020
Schedule of Available-for-sale Securities [Line Items] |  |  |
Tax exempt interest income on available-for-sale securities | $ 11.9 | $ 10.2 | $ 10.7
Realized loss on trading securities | $ (7.0) |  |
Mortgage Backed Securities And Collateralized Mortgage Obligations |  |  |
Schedule of Available-for-sale Securities [Line Items] |  |  |
Weighted average yield | 3.08% | 1.82% |
U.S. Treasury securities | Not Designated as Hedging Instrument, Economic Hedge |  |  |
Schedule of Available-for-sale Securities [Line Items] |  |  |
Trading securities - U.S. Treasury securities | $ 19.0 |  |

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