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LOANS AND ALLOWANCE FOR CREDIT LOSSES - Impaired Loans (Details) - USD ($) $ in Thousands | 3 Months Ended | 6 Months Ended |
--- | --- | --- | ---
Jun. 30, 2023 | Jun. 30, 2022 | Jun. 30, 2023 | Jun. 30, 2022 | Dec. 31, 2022
Impaired Financing Receivable, Unpaid Principal Balance [Abstract] |  |  |  |  |
Total |  |  |  |  | $ 7,548
Impaired Financing Receivable, Recorded Investment [Abstract] |  |  |  |  |
Total |  |  |  |  | 7,522
Allowance for Loan Losses Allocated |  |  |  |  | 1,147
Average Amortized Cost Basis |  |  |  |  |
Average recorded investment, total | $ 6,386 | $ 8,856 | $ 6,751 | $ 9,754 |
Interest Income Recognized |  |  |  |  |
Total | 13 | 22 | 21 | 69 |
Residential Mortgages |  |  |  |  |
Impaired Financing Receivable, Unpaid Principal Balance [Abstract] |  |  |  |  |
With no related allowance recorded |  |  |  |  | 767
Impaired Financing Receivable, Recorded Investment [Abstract] |  |  |  |  |
With no related allowance recorded |  |  |  |  | 760
Average Amortized Cost Basis |  |  |  |  |
With no related allowance recorded | 358 | 909 | 479 | 895 |
Interest Income Recognized |  |  |  |  |
With no related allowance recorded | 0 | 11 | 0 | 22 |
Construction | Commercial Mortgages |  |  |  |  |
Impaired Financing Receivable, Unpaid Principal Balance [Abstract] |  |  |  |  |
With no related allowance recorded |  |  |  |  | 5
Impaired Financing Receivable, Recorded Investment [Abstract] |  |  |  |  |
With no related allowance recorded |  |  |  |  | 5
Average Amortized Cost Basis |  |  |  |  |
With no related allowance recorded | 0 | 105 | 2 | 113 |
Interest Income Recognized |  |  |  |  |
With no related allowance recorded | 0 | 1 | 0 | 2 |
Commercial mortgages, other | Commercial Mortgages |  |  |  |  |
Impaired Financing Receivable, Unpaid Principal Balance [Abstract] |  |  |  |  |
With no related allowance recorded |  |  |  |  | 4,346
With an allowance recorded |  |  |  |  | 38
Impaired Financing Receivable, Recorded Investment [Abstract] |  |  |  |  |
With no related allowance recorded |  |  |  |  | 4,341
With an allowance recorded |  |  |  |  | 38
Allowance for Loan Losses Allocated |  |  |  |  | 38
Average Amortized Cost Basis |  |  |  |  |
With no related allowance recorded | 3,992 | 4,086 | 4,138 | 4,149 |
With an allowance recorded | 34 | 1,326 | 35 | 2,065 |
Interest Income Recognized |  |  |  |  |
With no related allowance recorded | 8 | 7 | 14 | 14 |
With an allowance recorded | 0 | 0 | 0 | 21 |
Home equity lines & loans | Consumer Loans |  |  |  |  |
Impaired Financing Receivable, Unpaid Principal Balance [Abstract] |  |  |  |  |
With no related allowance recorded |  |  |  |  | 154
With an allowance recorded |  |  |  |  | 126
Impaired Financing Receivable, Recorded Investment [Abstract] |  |  |  |  |
With no related allowance recorded |  |  |  |  | 138
With an allowance recorded |  |  |  |  | 127
Allowance for Loan Losses Allocated |  |  |  |  | 31
Average Amortized Cost Basis |  |  |  |  |
With no related allowance recorded | 178 | 157 | 165 | 161 |
With an allowance recorded | 78 | 139 | 63 | 141 |
Interest Income Recognized |  |  |  |  |
With no related allowance recorded | 0 | 0 | 0 | 2 |
With an allowance recorded | 3 | 0 | 3 | 0 |
Commercial and industrial | Commercial and Agricultural |  |  |  |  |
Impaired Financing Receivable, Unpaid Principal Balance [Abstract] |  |  |  |  |
With no related allowance recorded |  |  |  |  | 1,026
With an allowance recorded |  |  |  |  | 1,086
Impaired Financing Receivable, Recorded Investment [Abstract] |  |  |  |  |
With no related allowance recorded |  |  |  |  | 1,025
With an allowance recorded |  |  |  |  | 1,088
Allowance for Loan Losses Allocated |  |  |  |  | $ 1,078
Average Amortized Cost Basis |  |  |  |  |
With no related allowance recorded | 516 | 765 | 686 | 825 |
With an allowance recorded | 1,230 | 1,369 | 1,183 | 1,405 |
Interest Income Recognized |  |  |  |  |
With no related allowance recorded | 0 | 0 | 0 | 3 |
With an allowance recorded | $ 2 | $ 3 | $ 4 | $ 5 |

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