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INVESTMENT SECURITIES - Additional Information (Details) - USD ($) $ in Millions	9 Months Ended
	Sep. 30, 2025	Dec. 31, 2024
Investment Securities Pledged as Collateral
Accrued interest and fees receivable	$ 4.1
Investment securities pledged to collateralize certain deposits and borrowings	$ 2,450.0	$ 2,270.0
Percentage of first half of subscription on FRB stock	0.50%
Percentage of remaining half of subscription on FRB stock	0.50%
U.S. Treasury and agency securities | Securities Sold under Agreements to Repurchase
Investment Securities Pledged as Collateral
Investment securities pledged to collateralize certain deposits and borrowings	$ 319.2	$ 362.1

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- Definition

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- Definition

For an unclassified balance sheet, the amount of fees and other revenue, excluding investment income receivable, earned but not yet received, which were recognized in conformity with revenue recognition criteria based on estimates or specific contractual terms.

+ References

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Amount, after allowance for credit loss, of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), investment in debt security measured at amortized cost (held-to-maturity), and investment in debt security measured at fair value with change in fair value recognized in net income (trading).

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