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SECURITIES AVAILABLE FOR SALE, HELD TO MATURITY, AND EQUITY SECURITIES - Narrative (Details) | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2024 USD ($) security | Sep. 30, 2023 USD ($) | Sep. 30, 2024 USD ($) security | Sep. 30, 2023 USD ($)
Investment Holdings [Line Items] |  |  |  |
Purchases of securities available for sale | $ | $ 46,400,000 | $ 7,800,000 | $ 54,206,000 | $ 44,586,000
Proceeds from sale of available-for-sale securities | $ |  | 0 | 361,871,000 | 0
Debt securities, available-for-sale, realized gain | $ | 0 |  | 5,100,000 |
Debt securities, available-for-sale, realized loss | $ | 0 |  | 54,900,000 |
(Loss) on sale of AFS securities, net | $ | $ 0 | $ 0 | $ (49,909,000) | $ 0
Municipal bonds and obligations |  |  |  |
Investment Holdings [Line Items] |  |  |  |
Available-for-sale, securities in unrealized loss positions | 40 |  | 40 |
Debt securities, continuous unrealized loss position, qualitative disclosure, aggregate losses percentage |  |  | 3.60% |
Number of securities | 91 |  | 91 |
Held-to-maturity, securities in unrealized loss positions | 111 |  | 111 |
Number of securities in the portfolio of HTM | 161 |  | 161 |
Aggregate unrealized losses as a percentage of the amortized cost of the securities in unrealized loss positions |  |  | 10.20% |
Agency collateralized mortgage obligations |  |  |  |
Investment Holdings [Line Items] |  |  |  |
Available-for-sale, securities in unrealized loss positions | 37 |  | 37 |
Debt securities, continuous unrealized loss position, qualitative disclosure, aggregate losses percentage |  |  | 21.10% |
Number of securities | 40 |  | 40 |
Held-to-maturity, securities in unrealized loss positions | 12 |  | 12 |
Number of securities in the portfolio of HTM | 12 |  | 12 |
Aggregate unrealized losses as a percentage of the amortized cost of the securities in unrealized loss positions |  |  | 14.90% |
Agency commercial mortgage-backed securities |  |  |  |
Investment Holdings [Line Items] |  |  |  |
Available-for-sale, securities in unrealized loss positions | 28 |  | 28 |
Debt securities, continuous unrealized loss position, qualitative disclosure, aggregate losses percentage |  |  | 16.40% |
Number of securities | 28 |  | 28 |
Held-to-maturity, securities in unrealized loss positions | 17 |  | 17 |
Number of securities in the portfolio of HTM | 17 |  | 17 |
Aggregate unrealized losses as a percentage of the amortized cost of the securities in unrealized loss positions |  |  | 17.00% |
Corporate bonds |  |  |  |
Investment Holdings [Line Items] |  |  |  |
Available-for-sale, securities in unrealized loss positions | 13 |  | 13 |
Debt securities, continuous unrealized loss position, qualitative disclosure, aggregate losses percentage |  |  | 9.00% |
Number of securities | 14 |  | 14 |
Other bonds and obligations |  |  |  |
Investment Holdings [Line Items] |  |  |  |
Available-for-sale, securities in unrealized loss positions | 2 |  | 2 |
Debt securities, continuous unrealized loss position, qualitative disclosure, aggregate losses percentage |  |  | 18.30% |
Number of securities | 3 |  | 3 |
Tax advantaged economic development bonds |  |  |  |
Investment Holdings [Line Items] |  |  |  |
Held-to-maturity, securities in unrealized loss positions | 2 |  | 2 |
Number of securities in the portfolio of HTM | 2 |  | 2 |
Aggregate unrealized losses as a percentage of the amortized cost of the securities in unrealized loss positions |  |  | 2.90% |

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