INVESTMENT SECURITIES - Narrative (Details) - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023	Jan. 01, 2021
Schedule Of Available For Sale Securities And Held To Maturity Securities [Line Items]
Accrued interest on investment securities	$ 22,600	$ 25,200
Allowance for credit losses	245	245
Carrying value of securities pledged as collateral	1,700,000	1,800,000
Securities sold under repurchase agreements	152,000	181,400
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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