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INVESTMENT SECURITIES - Narrative (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023
Schedule of Available-for-sale Securities [Line Items]
Tax exempt interest income on available-for-sale securities	$ 11.1	$ 11.3
Realized loss on trading securities	$ (1.7)	$ (0.5)
Mortgage Backed Securities and Collateralized Mortgage Obligations
Schedule of Available-for-sale Securities [Line Items]
Weighted average yield	3.01%	3.21%
U.S. Treasury securities | Not Designated as Hedging Instrument, Economic Hedge
Schedule of Available-for-sale Securities [Line Items]
Trading securities - U.S. Treasury securities	$ 35.0	$ 25.0

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