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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 | 3 Months Ended | 12 Months Ended
--- | --- | ---
Mar. 31, 2023 USD ($) | Dec. 31, 2022 USD ($)
State and municipal securities | Discounted cash flow |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Fair Value | $ 3,427 | $ 3,404
State and municipal securities | Discounted cash flow | Minimum |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Maturity/Call date | 1 month | 1 month
US Muni BQ curve | A- | A-
State and municipal securities | Discounted cash flow | Maximum |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Maturity/Call date | 15 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] |  |
Debt securities, available-for-sale, measurement input | 0.031 | 0.004
State and municipal securities | Discounted cash flow | Discount rate | Maximum |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Debt securities, available-for-sale, measurement input | 0.044 | 0.04
State and municipal securities | Discounted cash flow | Weighted-average coupon | Weighted-average |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Debt securities, available-for-sale, measurement input | 0.034 | 0.034
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] |  |
Debt securities, available-for-sale, 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] |  |
Discount rate description | 3 month LIBOR | 3 month LIBOR
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] |  |
Debt securities, available-for-sale, measurement input | 200 | 200
Collateral dependent loans | Collateral based measurements |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Fair Value | $ 51,757 | $ 55,290
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] |  |
Collateral dependent loans, 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] |  |
Collateral dependent loans, measurement input | 0.10 | 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] |  |
Collateral dependent loans, measurement input | 0.015 | 0.011

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