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LOANS AND ALLOWANCE FOR LOAN LOSSES - Collateral Dependent (Details) - USD ($) $ in Thousands | Mar. 31, 2023 | Dec. 31, 2022 | Mar. 31, 2022 | Dec. 31, 2021
--- | --- | --- | --- | ---
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |  |  |  |
Loans individually analyzed | $ 6,837 |  | $ 7,482 |  |  |
Allowance for credit losses | 20,075 | [1] | 19,659 | [1] | $ 19,928 | $ 21,025
Commercial and Agricultural |  |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |  |  |  |
Loans individually analyzed | 1,779 |  | 2,112 |  |  |
Allowance for credit losses | 4,053 |  | 3,373 |  | 3,483 | 3,591
Commercial Mortgages |  |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |  |  |  |
Loans individually analyzed | 4,089 |  | 4,383 |  |  |
Allowance for credit losses | 10,983 |  | 11,576 |  | 12,964 | 13,556
Residential Mortgages |  |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |  |  |  |
Loans individually analyzed | 715 |  | 723 |  |  |
Allowance for credit losses | 1,892 |  | 1,845 |  | 1,606 | 1,803
Consumer Loans |  |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |  |  |  |
Loans individually analyzed | 254 |  | 264 |  |  |
Allowance for credit losses | 3,147 |  | $ 2,865 |  | $ 1,875 | $ 2,075
Collateral Pledged |  |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |  |  |  |
Loans individually analyzed | 5,955 |  |  |  |  |
Allowance for credit losses | 204 |  |  |  |  |
Commercial Real Estate And Business Assets | Commercial and Agricultural | Commercial and industrial |  |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |  |  |  |
Loans individually analyzed | 573 |  |  |  |  |
Allowance for credit losses | 168 |  |  |  |  |
Commercial Real Estate | Commercial Mortgages | Commercial mortgages, other |  |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |  |  |  |
Loans individually analyzed | 4,413 |  |  |  |  |
Allowance for credit losses | 36 |  |  |  |  |
Residential Real Estate | Residential Mortgages |  |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |  |  |  |
Loans individually analyzed | 715 |  |  |  |  |
Allowance for credit losses | 0 |  |  |  |  |
Residential Real Estate | Consumer Loans | Home equity lines and loans |  |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |  |  |  |
Loans individually analyzed | 254 |  |  |  |  |
Allowance for credit losses | $ 0 |  |  |  |  |
[1] | Effective January 1, 2023, the allowance calculation is based upon Current Expected Credit loss methodology. Prior to January 1, 2023, the allowance calculation was based upon incurred loss methodology. Refer to Note 1 for further discussion.

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