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LOANS AND ALLOWANCE FOR CREDIT LOSSES - Collateral Dependent (Details) - USD ($) $ in Thousands | Jun. 30, 2023 | Mar. 31, 2023 | Dec. 31, 2022 | Jun. 30, 2022 | Mar. 31, 2022 | Dec. 31, 2021
--- | --- | --- | --- | --- | --- | ---
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |  |  |  |  |  |
Amortized Cost Basis | $ 5,937 |  |  | $ 7,482 |  |  |  |
Related Allowance | 20,172 | [1] | $ 20,075 | 19,659 | [1] | $ 17,485 | $ 19,928 | $ 21,025
Commercial and Agricultural |  |  |  |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |  |  |  |  |  |
Amortized Cost Basis | 1,714 |  |  | 2,112 |  |  |  |
Related Allowance | 4,121 |  | 4,053 | 3,373 |  | 3,564 | 3,485 | 3,591
Commercial Mortgages |  |  |  |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |  |  |  |  |  |
Amortized Cost Basis | 3,964 |  |  | 4,383 |  |  |  |
Related Allowance | 10,994 |  | 10,983 | 11,576 |  | 10,314 | 12,963 | 13,556
Consumer Loans |  |  |  |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |  |  |  |  |  |
Amortized Cost Basis | 259 |  |  | 264 |  |  |  |
Related Allowance | 3,152 |  | $ 3,147 | $ 2,865 |  | $ 1,893 | $ 1,874 | $ 2,075
Collateral Pledged |  |  |  |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |  |  |  |  |  |
Amortized Cost Basis | 5,096 |  |  |  |  |  |  |
Related Allowance | 250 |  |  |  |  |  |  |
Commercial Real Estate And Business Assets | Commercial and Agricultural | Commercial and industrial |  |  |  |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |  |  |  |  |  |
Amortized Cost Basis | 570 |  |  |  |  |  |  |
Related Allowance | 156 |  |  |  |  |  |  |
Commercial Real Estate | Commercial Mortgages | Commercial mortgages, other |  |  |  |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |  |  |  |  |  |
Amortized Cost Basis | 4,267 |  |  |  |  |  |  |
Related Allowance | 33 |  |  |  |  |  |  |
Residential Real Estate | Consumer Loans | Home equity lines and loans |  |  |  |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |  |  |  |  |  |
Amortized Cost Basis | 259 |  |  |  |  |  |  |
Related Allowance | $ 61 |  |  |  |  |  |  |
[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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