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INVESTMENT SECURITIES - Narrative (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023	Dec. 31, 2023
Debt Securities, Available-for-sale [Line Items]
Trading gain (losses) recorded in servicing income	$ (0.6)	$ 0.6
Tax exempt interest income on available-for-sale securities	$ 2.8	$ 2.8
Mortgage Backed Securities and Collateralized Mortgage Obligations
Debt Securities, Available-for-sale [Line Items]
Weighted average yield	3.09%		3.21%
US Treasury Notes Securities | Not Designated as Hedging Instrument, Economic Hedge
Debt Securities, Available-for-sale [Line Items]
Trading securities	$ 28.0		$ 25.0

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Available for sale securities debt maturities without single maturity date weighted average yield.

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