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SECURITIES - Additional Information (Details) $ in Thousands | 3 Months Ended | 12 Months Ended |
--- | --- | --- | ---
Mar. 31, 2017 security | Dec. 31, 2023 USD ($) segment security | Dec. 31, 2022 USD ($) | Dec. 31, 2021 USD ($) | Dec. 31, 2020 USD ($)
Debt Securities, Available-for-sale [Line Items] |  |  |  |  |
Securities pledged as collateral |  | $ 992,100 | $ 946,300 |  |
Gain on sale of investments |  | 1 | 6 | $ 274 |
Loss on sale of investments |  | $ 2 | 3 | 160 |
Number of CDO other-than-temporary impaired | security |  | 3 |  |  |
Number of CDO called | security | 1 |  |  |  |
Number of investment securities segregation for impairment evaluation | segment |  | 2 |  |  |
Debt Securities, Available-for-sale, Unrealized Loss Position, Number of Positions | segment |  | 844 |  |  |
Cumulative credit loss charges recorded through earnings to date |  | $ 2,974 | 2,974 | $ 2,974 | $ 2,974
Unrealized losses |  | 157,845 | $ 172,134 |  |
Collateralized debt obligations |  |  |  |  |
Debt Securities, Available-for-sale [Line Items] |  |  |  |  |
Contractual balance |  | 3,700 |  |  |
Reduced balance |  | 3,000 |  |  |
Interest payment received |  | 750 |  |  |
Other comprehensive income net |  | 3,000 |  |  |
Cumulative credit loss charges recorded through earnings to date |  | $ 3,000 |  |  |

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