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INVESTMENT SECURITIES - Additional Information (Details) - USD ($)	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Schedule Of Securities [Line Items]
Debt securities available for sale, allowance for credit losses	$ 0	$ 0
Debt securities, available-for-sale, accrued interest, after allowance for credit loss	16,200,000	14,300,000
Debt securities held to maturity, allowance for credit losses	290,000	250,000
Debt securities, held-to-maturity, accrued interest, after allowance for credit loss	15,700,000	14,600,000
Debt securities, available for sale, sold		231,400,000	$ 648,700,000
Debt securities, available-for-sale, realized loss (gain)		$ 34,000,000.0	$ 67,400,000
Debt securities, available-for-sale, average yield		1.41%	1.08%
Debt securities, available-for-sale, average yield, higher comparison		4.78%	3.50%
Municipal bond portfolio, value	1,000,000,000.0
Corporate bond portfolio, at carrying value	74,000,000.0
Municipal Bonds | Weighted Average
Schedule Of Securities [Line Items]
Average holding size of securities in bond portfolio	$ 2,500,000
Municipal Bonds | Credit Concentration Risk | General Obligation Bonds | A Rating or Better
Schedule Of Securities [Line Items]
Percentage of portfolio	97.00%
Municipal Bonds | Geographic Concentration Risk | Pennsylvania, Ohio and Maryland
Schedule Of Securities [Line Items]
Percentage of portfolio	59.00%
Corporate Bond Securities | Weighted Average
Schedule Of Securities [Line Items]
Average holding size of securities in bond portfolio	$ 3,900,000
US government
Schedule Of Securities [Line Items]
Unrealized loss on debt securities, available-for-sale and held-to-maturity, backed or sponsored percentage	86.30%
States of the U.S. and political subdivisions (municipals)
Schedule Of Securities [Line Items]
Debt securities held to maturity, allowance for credit losses	$ 60,000.00	$ 70,000.00
Other debt securities
Schedule Of Securities [Line Items]
Debt securities held to maturity, allowance for credit losses	$ 230,000	$ 180,000

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