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INVESTMENT SECURITIES - Additional Information (Details) - USD ($) $ in Thousands | 3 Months Ended |
--- | --- | ---
Mar. 31, 2024 | Mar. 31, 2023 | Dec. 31, 2023
Investment Securities Pledged as Collateral |  |  |
Accrued interest and fees receivable | $ 3,300 |  |
Investment securities pledged to collateralize certain deposits and borrowings | 2,760,000 |  | $ 2,140,000
Gross realized losses | 0 | $ (52,329) |
Proceeds from sales of securities | 0 | 733,789 |
U.S. Treasury and agency securities |  |  |
Investment Securities Pledged as Collateral |  |  |
Book value of available-for-sale |  | 786,100 |
Gross realized losses |  | 52,300 |
Proceeds from sales of securities |  | $ 733,800 |
U.S. Treasury and agency securities | Securities Sold under Agreements to Repurchase |  |  |
Investment Securities Pledged as Collateral |  |  |
Investment securities pledged to collateralize certain deposits and borrowings | $ 393,500 |  | $ 598,900

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