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SECURITIES - Narrative (Details) - USD ($) $ in Thousands | 3 Months Ended | 12 Months Ended
--- | --- | ---
Mar. 31, 2024 | Mar. 31, 2023 | Dec. 31, 2023
Debt and Equity Securities, FV-NI [Line Items] |  |  |
Transfer from securities held-to-maturity | $ 0 | $ 0 |
Number of holdings of securities of any one issuer in an amount greater than 10% of stockholders equity | 0 |  | 0
Threshold for disclosure percentage | 10.00% |  | 10.00%
Available for sale debt securities, unrealized loss position due to credit | $ 0 |  |
Allowance for credit losses on available for sale debt securities | 0 |  |
Accrued interest receivable on securities | 3,300 |  | $ 5,300
Unrealized losses are related to credit losses | 0 |  |
Securities pledged |  |  |
Debt and Equity Securities, FV-NI [Line Items] |  |  |
Carrying amount of securities pledged | $ 616,700 |  | $ 457,700

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