INVESTMENT SECURITIES - Narrative (Details) - USD ($) $ in Thousands	Sep. 30, 2023	Dec. 31, 2022	Jan. 01, 2021
Schedule Of Available For Sale Securities And Held To Maturity Securities [Line Items]
Accrued interest on investment securities	$ 23,200	$ 29,500
Allowance for credit losses	245	245
Carrying value of securities pledged as collateral	1,700,000	941,300
Securities sold under repurchase agreements	187,300	196,700
State and municipal
Schedule Of Available For Sale Securities And Held To Maturity Securities [Line Items]
Allowance for credit losses	$ 245	$ 245
State and municipal \| CECL adoption
Schedule Of Available For Sale Securities And Held To Maturity Securities [Line Items]
Allowance for credit losses			$ 245

Debt Securities, Available-for-sale and Held-to-maturity, Accrued Interest

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Schedule Of Available For Sale Securities And Held To Maturity Securities

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Amount, excluding accrued interest, of allowance for credit loss on investment in debt security measured at amortized cost (held-to-maturity).

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Amount of asset associated with funds outstanding borrowed in the form of a security repurchase agreement between the entity and another party for the sale and repurchase of identical or substantially the same securities at a date certain for a specified price.

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