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SECURITIES AVAILABLE FOR SALE, HELD TO MATURITY, AND EQUITY SECURITIES - Narrative (Details) | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2023 USD ($) security | Jun. 30, 2022 USD ($) | Jun. 30, 2023 USD ($) security | Jun. 30, 2022 USD ($)
Investment Holdings [Line Items] |  |  |  |
Purchases of securities available for sale | $ | $ 7,900,000 | $ 0 | $ 36,798,000 | $ 386,637,000
Proceeds from sale of available-for-sale securities | $ | $ 0 | 150,000,000 | $ 0 | 149,994,000
Debt securities, available-for-sale, gain (loss) | $ |  | $ 6,000 |  | $ 6,000
Municipal bonds and obligations |  |  |  |
Investment Holdings [Line Items] |  |  |  |
Available-for-sale, securities in unrealized loss positions | 53 |  | 53 |
Number of securities | 94 |  | 94 |
Debt securities, continuous unrealized loss position, qualitative disclosure, aggregate losses percentage |  |  | 5.50% |
Held-to-maturity, securities in unrealized loss positions | 115 |  | 115 |
Held-to-maturity securities portfolio, number of securities | 183 |  | 183 |
Aggregate losses, percent |  |  | 11.50% |
Agency collateralized mortgage obligations |  |  |  |
Investment Holdings [Line Items] |  |  |  |
Available-for-sale, securities in unrealized loss positions | 240 |  | 240 |
Number of securities | 242 |  | 242 |
Debt securities, continuous unrealized loss position, qualitative disclosure, aggregate losses percentage |  |  | 16.90% |
Held-to-maturity, securities in unrealized loss positions | 13 |  | 13 |
Held-to-maturity securities portfolio, number of securities | 13 |  | 13 |
Aggregate losses, percent |  |  | 17.00% |
Agency commercial mortgage-backed securities |  |  |  |
Investment Holdings [Line Items] |  |  |  |
Available-for-sale, securities in unrealized loss positions | 137 |  | 137 |
Number of securities | 139 |  | 139 |
Debt securities, continuous unrealized loss position, qualitative disclosure, aggregate losses percentage |  |  | 15.10% |
Held-to-maturity, securities in unrealized loss positions | 17 |  | 17 |
Held-to-maturity securities portfolio, number of securities | 17 |  | 17 |
Aggregate losses, percent |  |  | 18.90% |
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 |  |  | 11.70% |
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 | 1 |  | 1 |
Held-to-maturity securities portfolio, number of securities | 2 |  | 2 |
Aggregate losses, percent |  |  | 8.90% |

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