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LOANS AND ALLOWANCE FOR CREDIT LOSSES - Collateral Dependent (Details) - USD ($) $ in Thousands | Jun. 30, 2024 | Mar. 31, 2024 | Dec. 31, 2023 | Jun. 30, 2023 | Mar. 31, 2023 | Dec. 31, 2022
--- | --- | --- | --- | --- | --- | ---
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |  |  |  |
Amortized Cost Basis | $ 6,049 |  | $ 8,035 |  |  |
Related Allowance | 21,031 | $ 20,471 | 22,517 | $ 20,172 | $ 20,075 | $ 19,659
Commercial and Industrial |  |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |  |  |  |
Amortized Cost Basis | 2,102 |  | 2,067 |  |  |
Related Allowance | 4,894 | 4,516 | 5,055 | 4,121 | 4,053 | 3,373
Commercial Mortgages |  |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |  |  |  |
Amortized Cost Basis | 3,947 |  | 5,968 |  |  |
Related Allowance | 10,530 | $ 10,367 | 12,026 | $ 10,994 | $ 10,983 | $ 11,576
Commercial Mortgages | Construction Loans |  |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |  |  |  |
Amortized Cost Basis | 2,258 |  | 2,209 |  |  |
Related Allowance | 0 |  | 0 |  |  |
Collateral Pledged |  |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |  |  |  |
Amortized Cost Basis | 4,242 |  | 6,347 |  |  |
Related Allowance | 250 |  | 267 |  |  |
Commercial Real Estate And Business Assets | Commercial and Industrial | Commercial and industrial |  |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |  |  |  |
Amortized Cost Basis | 295 |  | 379 |  |  |
Related Allowance | 229 |  | 240 |  |  |
Commercial Real Estate and Residential Real Estate | Commercial Mortgages | Commercial mortgages, other |  |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |  |  |  |
Amortized Cost Basis | 1,689 |  | 3,759 |  |  |
Related Allowance | $ 21 |  | $ 27 |  |  |

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