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FAIR VALUES OF FINANCIAL INSTRUMENTS - Unobservable Inputs Used in Recurring and Nonrecurring Level 3 Fair Value Measurements Other Than Goodwill (Details) - Significant Unobservable Inputs (Level 3) $ in Thousands | 9 Months Ended | 12 Months Ended
--- | --- | ---
Sep. 30, 2024 USD ($) | Dec. 31, 2023 USD ($)
State and municipal securities | Discounted cash flow |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Fair Value | $ 2,446 | $ 3,275
State and municipal securities | Discounted cash flow | Minimum |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Maturity/Call date | 1 month | 1 month
State and municipal securities | Discounted cash flow | Maximum |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Maturity/Call date | 6 years | 15 years
US Muni BQ curve | BBB | BBB
State and municipal securities | Discounted cash flow | Discount rate | Minimum |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Measurement input | 0.031 | 0.036
State and municipal securities | Discounted cash flow | Discount rate | Maximum |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Measurement input | 0.043 | 0.047
State and municipal securities | Discounted cash flow | Weighted-average coupon | Weighted-average |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Measurement input | 0.036 | 0.033
Corporate obligations and U.S. Government-sponsored mortgage-backed securities | Discounted cash flow |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Fair Value | $ 35 | $ 35
Corporate obligations and U.S. Government-sponsored mortgage-backed securities | Discounted cash flow | Weighted-average coupon | Weighted-average |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Measurement input | 0 | 0
Corporate obligations and U.S. Government-sponsored mortgage-backed securities | Discounted cash flow | Risk free rate |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Measurement input | 0.0026 | 0.0026
Corporate obligations and U.S. Government-sponsored mortgage-backed securities | Discounted cash flow | plus premium for illiquidity (basis points) |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Measurement input | 0.0200 | 0.0200
Collateral dependent loans | Collateral based measurements |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Fair Value | $ 55,211 | $ 55,020
Collateral dependent loans | Collateral based measurements | Discount to reflect current market conditions and ultimate collectability | Minimum |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Measurement input | 0 | 0
Collateral dependent loans | Collateral based measurements | Discount to reflect current market conditions and ultimate collectability | Maximum |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Measurement input | 0.15 | 0.10
Collateral dependent loans | Collateral based measurements | Discount to reflect current market conditions and ultimate collectability | Weighted-average |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Measurement input | 0.121 | 0.041

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