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FAIR VALUE MEASUREMENTS - Additional Information (Details) - USD ($) $ in Millions | 12 Months Ended
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Dec. 31, 2025 | Dec. 31, 2024
Fair Value Measurements Disclosure [Line Items] |  |
Percentage of securities using market-based information | 100.00% |
Collateral dependent loans, allowance for credit loss | $ 30.4 |
Provision for fair value measurements included in allowance for loan losses | $ 58.4 |
Short-term borrowings approximate fair value for amounts that mature, days, less than | 90 days |
Fair value, measurements, recurring |  |
Fair Value Measurements Disclosure [Line Items] |  |
Transfer into (from) level 3 | $ 84.6 |
Fair value, measurements, nonrecurring |  |
Fair Value Measurements Disclosure [Line Items] |  |
Collateral dependent loans carrying value | 125.5 |
Carrying amount of OREO | 0.9 |
Valuation allowance of OREO | 0.6 |
Valuation allowance loss in earnings | 0.7 |
Mortgage Servicing Rights | Fair value, measurements, nonrecurring |  |
Fair Value Measurements Disclosure [Line Items] |  |
Loan servicing rights | 1.9 |
Valuation allowance for impairment of recognized servicing assets | 0.1 |
SBA-Guaranteed Loan Servicing | Fair value, measurements, nonrecurring |  |
Fair Value Measurements Disclosure [Line Items] |  |
Loan servicing rights | 1.7 |
Valuation allowance for impairment of recognized servicing assets | 0.4 | $ 0.6
Valuation allowance for impairment of recognized servicing assets, recoveries | 0.2 |
Minimum | Commercial Loan |  |
Fair Value Measurements Disclosure [Line Items] |  |
Financing receivable, individual reserves in default, threshold | 1.0 |
Maximum | Commercial and Consumer Loans |  |
Fair Value Measurements Disclosure [Line Items] |  |
Financing receivable, individual reserves in default, threshold | $ 1.0 |

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- Definition Amount of gain (loss) included in earnings relating to other real estate owned that is measured at fair value on a non-recurring basis. + References No definition available. + Details
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