| **LOANS AND ALLOWANCE - Composition of Loan Portfolio by Loan Class (Details) - USD ($) $ in Thousands** | Sep. 30, 2022 | Dec. 31, 2021 |
|----------------------------------------------------------------------------------------------------------|---------------|---------------|
| **Financing Receivable, Credit Quality Indicator [Line Items]**                                          |          |          |
| Loans                                                                                                    | $ 11,650,002  | $ 9,241,861   |
| Commercial and industrial loans                                                                          |          |          |
| **Financing Receivable, Credit Quality Indicator [Line Items]**                                          |          |          |
| Loans                                                                                                    | 3,330,529     | 2,714,565     |
| Agricultural land, production and other loans to farmers                                                 |          |          |
| **Financing Receivable, Credit Quality Indicator [Line Items]**                                          |          |          |
| Loans                                                                                                    | 221,954       | 246,442       |
| Construction                                                                                             |          |          |
| **Financing Receivable, Credit Quality Indicator [Line Items]**                                          |          |          |
| Loans                                                                                                    | 828,923       | 523,066       |
| Commercial real estate, non-owner occupied                                                               |          |          |
| **Financing Receivable, Credit Quality Indicator [Line Items]**                                          |          |          |
| Loans                                                                                                    | 2,299,272     | 2,135,459     |
| Commercial real estate, owner occupied                                                                   |          |          |
| **Financing Receivable, Credit Quality Indicator [Line Items]**                                          |          |          |
| Loans                                                                                                    | 1,268,567     | 986,720       |
| Residential                                                                                              |          |          |
| **Financing Receivable, Credit Quality Indicator [Line Items]**                                          |          |          |
| Loans                                                                                                    | 1,990,668     | 1,159,127     |
| Home equity                                                                                              |          |          |
| **Financing Receivable, Credit Quality Indicator [Line Items]**                                          |          |          |
| Loans                                                                                                    | 621,619       | 523,754       |
| Individuals' loans for household and other personal expenditures                                         |          |          |
| **Financing Receivable, Credit Quality Indicator [Line Items]**                                          |          |          |
| Loans                                                                                                    | 173,225       | 146,092       |
| Public finance and other commercial loans                                                                |          |          |
| **Financing Receivable, Credit Quality Indicator [Line Items]**                                          |          |          |
| Loans                                                                                                    | $ 915,245     | $ 806,636     |

| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                       |
|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amortized cost excluding accrued interest, before allowance for credit loss, of financing receivable. Excludes net investment in lease.
+ References
Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 20 -Section 50 -Paragraph 5 -Subparagraph (b) -URI https://asc.fasb.org/extlink&oid=124255953&loc=SL82919230-210447Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 20 -Section 45 -Paragraph 1 -URI https://asc.fasb.org/extlink&oid=124255206&loc=SL82895884-210446Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 20 -Section 50 -Paragraph 3B -URI https://asc.fasb.org/extlink&oid=124255953&loc=SL120267963-210447
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                      |
|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - 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.
+ References
No definition available.
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