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LOANS AND ALLOWANCE FOR CREDIT LOSSES - Collateral Dependent (Details) - USD ($) $ in Thousands | Dec. 31, 2023 | Dec. 31, 2022 | Dec. 31, 2021
--- | --- | --- | ---
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |  |  |
Amortized Cost Basis | $ 8,035 |  | $ 7,482 |  |
Related Allowance | 22,517 | [1] | 19,659 | [1] | $ 21,025
Commercial and Agricultural |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |  |  |
Amortized Cost Basis | 2,067 |  | 2,112 |  |
Related Allowance | 5,055 |  | 3,373 |  | 3,591
Commercial Mortgages |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |  |  |
Amortized Cost Basis | 5,968 |  | 4,383 |  |
Related Allowance | 12,026 |  | $ 11,576 |  | $ 13,556
Collateral Pledged |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |  |  |
Amortized Cost Basis | 6,347 |  |  |  |
Related Allowance | 267 |  |  |  |
Commercial Real Estate And Business Assets | Commercial and Agricultural | Commercial and industrial |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |  |  |
Amortized Cost Basis | 353 |  |  |  |
Related Allowance | 214 |  |  |  |
Commercial Real Estate And Business Assets | Commercial and Agricultural | Agricultural |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |  |  |
Amortized Cost Basis | 26 |  |  |  |
Related Allowance | 26 |  |  |  |
Commercial Real Estate and Residential Real Estate | Commercial Mortgages | Construction |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |  |  |
Amortized Cost Basis | 2,209 |  |  |  |
Related Allowance | 0 |  |  |  |
Commercial Real Estate and Residential Real Estate | Commercial Mortgages | Commercial mortgages, other |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |  |  |
Amortized Cost Basis | 3,759 |  |  |  |
Related Allowance | $ 27 |  |  |  |
[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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- Definition Amount excluding accrued interest, of allowance for credit loss on financing receivable. Excludes net investment in lease. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 326 -SubTopic 20 -Name Accounting Standards Codification -Section 45 -Paragraph 1 -Publisher FASB -URI https://asc.fasb.org//1943274/2147479344/326-20-45-1 + Details
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