| **LOANS AND ALLOWANCE - Non-Accrual Loans by Loan Class (Details) - USD ($) $ in Thousands** | Sep. 30, 2023 | Dec. 31, 2022 |
|----------------------------------------------------------------------------------------------|---------------|---------------|
| **Financing Receivable, Past Due [Line Items]**                                              |          |          |
| Nonaccrual Loans                                                                             | $ 53,102      | $ 42,324      |
| Nonaccrual Loans with no Allowance for Credit Losses                                         | 14,627        | 4,247         |
| Commercial and industrial loans                                                              |          |          |
| **Financing Receivable, Past Due [Line Items]**                                              |          |          |
| Nonaccrual Loans                                                                             | 14,737        | 3,292         |
| Nonaccrual Loans with no Allowance for Credit Losses                                         | 1,020         | 481           |
| Agricultural land, production and other loans to farmers                                     |          |          |
| **Financing Receivable, Past Due [Line Items]**                                              |          |          |
| Nonaccrual Loans                                                                             | 61            | 54            |
| Nonaccrual Loans with no Allowance for Credit Losses                                         | 0             | 0             |
| Construction                                                                                 |          |          |
| **Financing Receivable, Past Due [Line Items]**                                              |          |          |
| Nonaccrual Loans                                                                             | 724           | 12            |
| Nonaccrual Loans with no Allowance for Credit Losses                                         | 0             | 0             |
| Commercial real estate, non-owner occupied                                                   |          |          |
| **Financing Receivable, Past Due [Line Items]**                                              |          |          |
| Nonaccrual Loans                                                                             | 11,575        | 19,374        |
| Nonaccrual Loans with no Allowance for Credit Losses                                         | 11,293        | 280           |
| Commercial real estate, owner occupied                                                       |          |          |
| **Financing Receivable, Past Due [Line Items]**                                              |          |          |
| Nonaccrual Loans                                                                             | 3,125         | 3,550         |
| Nonaccrual Loans with no Allowance for Credit Losses                                         | 2,314         | 2,784         |
| Residential                                                                                  |          |          |
| **Financing Receivable, Past Due [Line Items]**                                              |          |          |
| Nonaccrual Loans                                                                             | 20,244        | 13,685        |
| Nonaccrual Loans with no Allowance for Credit Losses                                         | 0             | 702           |
| Home equity                                                                                  |          |          |
| **Financing Receivable, Past Due [Line Items]**                                              |          |          |
| Nonaccrual Loans                                                                             | 2,534         | 2,247         |
| Nonaccrual Loans with no Allowance for Credit Losses                                         | 0             | 0             |
| Individuals' loans for household and other personal expenditures                             |          |          |
| **Financing Receivable, Past Due [Line Items]**                                              |          |          |
| Nonaccrual Loans                                                                             | 102           | 110           |
| Nonaccrual Loans with no Allowance for Credit Losses                                         | $ 0           | $ 0           |

| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                           |
|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amortized cost of financing receivable on nonaccrual status with no allowance for credit loss. Excludes net investment in lease.
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|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amortized cost of financing receivable on nonaccrual status. Excludes net investment in lease.
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|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.
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