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SECURITIES AVAILABLE FOR SALE, HELD TO MATURITY, AND EQUITY SECURITIES - Narrative (Details) | 3 Months Ended
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Mar. 31, 2023 USD ($) security | Mar. 31, 2022 USD ($)
Investment Holdings [Line Items] |  |
Purchases of securities available for sale | $ | $ 28,899,000 | $ 386,636,000
Proceeds from sale of available-for-sale securities | $ | $ 0 | $ 0
Municipal bonds and obligations |  |
Investment Holdings [Line Items] |  |
Available-for-sale, securities in unrealized loss positions | 30 |
Number of securities | 94 |
Debt securities, continuous unrealized loss position, qualitative disclosure, aggregate losses percentage | 6.40% |
Held-to-maturity, securities in unrealized loss positions | 94 |
Held-to-maturity securities portfolio, number of securities | 186 |
Aggregate losses, percent | 13.40% |
Agency collateralized mortgage obligations |  |
Investment Holdings [Line Items] |  |
Available-for-sale, securities in unrealized loss positions | 243 |
Number of securities | 245 |
Debt securities, continuous unrealized loss position, qualitative disclosure, aggregate losses percentage | 14.20% |
Held-to-maturity, securities in unrealized loss positions | 13 |
Held-to-maturity securities portfolio, number of securities | 13 |
Aggregate losses, percent | 14.50% |
Agency commercial mortgage-backed securities |  |
Investment Holdings [Line Items] |  |
Available-for-sale, securities in unrealized loss positions | 136 |
Number of securities | 139 |
Debt securities, continuous unrealized loss position, qualitative disclosure, aggregate losses percentage | 13.80% |
Held-to-maturity, securities in unrealized loss positions | 17 |
Held-to-maturity securities portfolio, number of securities | 17 |
Aggregate losses, percent | 17.00% |
Corporate bonds |  |
Investment Holdings [Line Items] |  |
Available-for-sale, securities in unrealized loss positions | 14 |
Number of securities | 15 |
Debt securities, continuous unrealized loss position, qualitative disclosure, aggregate losses percentage | 7.90% |
Other bonds and obligations |  |
Investment Holdings [Line Items] |  |
Available-for-sale, securities in unrealized loss positions | 2 |
Number of securities | 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 |
Held-to-maturity securities portfolio, number of securities | 2 |
Aggregate losses, percent | 9.40% |

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