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INVESTMENT SECURITIES - Narrative (Details) - USD ($) $ in Thousands | Sep. 30, 2025 | Dec. 31, 2024
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Schedule Of Available For Sale Securities And Held To Maturity Securities [Line Items] |  |
Accrued interest on investment securities | $ 19,300 | $ 22,500
Allowance for credit losses | 245 | 245
Carrying value of securities pledged as collateral | 3,300,000 | 3,300,000
Securities sold under repurchase agreements | 143,800 | 173,000
State and municipal |  |
Schedule Of Available For Sale Securities And Held To Maturity Securities [Line Items] |  |
Allowance for credit losses | $ 245 | $ 245

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