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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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