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SECURITIES AVAILABLE FOR SALE, HELD TO MATURITY, AND MARKETABLE EQUITY SECURITIES - Narrative (Details) | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2022 USD ($) security | Sep. 30, 2021 USD ($) | Sep. 30, 2022 USD ($) security | Sep. 30, 2021 USD ($)
Investment Holdings [Line Items] |  |  |  |
Purchases of securities available for sale | $ | $ 41,400,000 | $ 160,000,000 | $ 428,068,000 | $ 428,950,000
Proceeds from sale of available-for-sale securities | $ | 0 | 0 | 149,994,000 | 0
Debt securities, available-for-sale, realized gain | $ | 0 | 0 | 6,000 | 0
Debt securities, available-for-sale, realized loss | $ | $ 0 | $ 0 | $ 0 | $ 0
Municipal bonds and obligations |  |  |  |
Investment Holdings [Line Items] |  |  |  |
Available-for-sale, securities in unrealized loss positions | 76 |  | 76 |
Number of securities | 95 |  | 95 |
Debt securities, continuous unrealized loss position, qualitative disclosure, aggregate losses percentage |  |  | 10.10% |
Held-to-maturity, securities in unrealized loss positions | 148 |  | 148 |
Held-to-maturity securities portfolio, number of securities | 192 |  | 192 |
Aggregate losses, percent |  |  | 16.10% |
Agency collateralized mortgage obligations |  |  |  |
Investment Holdings [Line Items] |  |  |  |
Available-for-sale, securities in unrealized loss positions | 245 |  | 245 |
Number of securities | 248 |  | 248 |
Debt securities, continuous unrealized loss position, qualitative disclosure, aggregate losses percentage |  |  | 15.00% |
Held-to-maturity, securities in unrealized loss positions | 13 |  | 13 |
Held-to-maturity securities portfolio, number of securities | 13 |  | 13 |
Aggregate losses, percent |  |  | 15.00% |
Agency commercial mortgage-backed securities |  |  |  |
Investment Holdings [Line Items] |  |  |  |
Available-for-sale, securities in unrealized loss positions | 136 |  | 136 |
Number of securities | 139 |  | 139 |
Debt securities, continuous unrealized loss position, qualitative disclosure, aggregate losses percentage |  |  | 15.20% |
Held-to-maturity, securities in unrealized loss positions | 17 |  | 17 |
Held-to-maturity securities portfolio, number of securities | 17 |  | 17 |
Aggregate losses, percent |  |  | 17.40% |
Corporate bonds |  |  |  |
Investment Holdings [Line Items] |  |  |  |
Available-for-sale, securities in unrealized loss positions | 14 |  | 14 |
Number of securities | 15 |  | 15 |
Debt securities, continuous unrealized loss position, qualitative disclosure, aggregate losses percentage |  |  | 5.50% |
Other bonds and obligations |  |  |  |
Investment Holdings [Line Items] |  |  |  |
Available-for-sale, securities in unrealized loss positions | 2 |  | 2 |
Number of securities | 3 |  | 3 |
Debt securities, continuous unrealized loss position, qualitative disclosure, aggregate losses percentage |  |  | 18.30% |
Tax advantaged economic development bonds |  |  |  |
Investment Holdings [Line Items] |  |  |  |
Held-to-maturity, securities in unrealized loss positions | 2 |  | 2 |
Held-to-maturity securities portfolio, number of securities | 3 |  | 3 |
Aggregate losses, percent |  |  | 10.30% |

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