| **LOANS AND ALLOWANCE - Amortized Cost Basis of Collateral Dependent Loans (Details) - USD ($) $ in Thousands** | 6 Months Ended |           |          |           |           |           |
|-----------------------------------------------------------------------------------------------------------------|----------------|-----------|----------|-----------|-----------|-----------|
||
| **Financing Receivable, Allowance for Credit Loss [Line Items]**                                                |           |      |     |      |      |      |
| Individually evaluated for impairment                                                                           | $ 83,479       |      | $ 78,302 |      |      |      |
| Allowance on Collateral Dependent Loans                                                                         | 221,147        | $ 223,052 | 223,277  | $ 226,275 | $ 195,984 | $ 195,397 |
| Commercial and industrial loans                                                                                 |           |      |     |      |      |      |
| **Financing Receivable, Allowance for Credit Loss [Line Items]**                                                |           |      |     |      |      |      |
| Individually evaluated for impairment                                                                           | 51,674         |      | 42,101   |      |      |      |
| Construction                                                                                                    |           |      |     |      |      |      |
| **Financing Receivable, Allowance for Credit Loss [Line Items]**                                                |           |      |     |      |      |      |
| Individually evaluated for impairment                                                                           | 9              |      | 10       |      |      |      |
| Commercial real estate, non-owner occupied                                                                      |           |      |     |      |      |      |
| **Financing Receivable, Allowance for Credit Loss [Line Items]**                                                |           |      |     |      |      |      |
| Individually evaluated for impairment                                                                           | 18,508         |      | 26,534   |      |      |      |
| Commercial real estate, owner occupied                                                                          |           |      |     |      |      |      |
| **Financing Receivable, Allowance for Credit Loss [Line Items]**                                                |           |      |     |      |      |      |
| Individually evaluated for impairment                                                                           | 11,448         |      | 6,986    |      |      |      |
| Residential                                                                                                     |           |      |     |      |      |      |
| **Financing Receivable, Allowance for Credit Loss [Line Items]**                                                |           |      |     |      |      |      |
| Individually evaluated for impairment                                                                           | 1,562          |      | 2,382    |      |      |      |
| Home equity                                                                                                     |           |      |     |      |      |      |
| **Financing Receivable, Allowance for Credit Loss [Line Items]**                                                |           |      |     |      |      |      |
| Individually evaluated for impairment                                                                           | 278            |      | 289      |      |      |      |
| Commercial Real Estate                                                                                          |           |      |     |      |      |      |
| **Financing Receivable, Allowance for Credit Loss [Line Items]**                                                |           |      |     |      |      |      |
| Individually evaluated for impairment                                                                           | 29,956         |      | 33,520   |      |      |      |
| Commercial Real Estate | Commercial and industrial loans                                                        |           |      |     |      |      |      |
| **Financing Receivable, Allowance for Credit Loss [Line Items]**                                                |           |      |     |      |      |      |
| Individually evaluated for impairment                                                                           | 0              |      | 0        |      |      |      |
| Commercial Real Estate | Construction                                                                           |           |      |     |      |      |      |
| **Financing Receivable, Allowance for Credit Loss [Line Items]**                                                |           |      |     |      |      |      |
| Individually evaluated for impairment                                                                           | 0              |      | 0        |      |      |      |
| Commercial Real Estate | Commercial real estate, non-owner occupied                                             |           |      |     |      |      |      |
| **Financing Receivable, Allowance for Credit Loss [Line Items]**                                                |           |      |     |      |      |      |
| Individually evaluated for impairment                                                                           | 18,508         |      | 26,534   |      |      |      |
| Commercial Real Estate | Commercial real estate, owner occupied                                                 |           |      |     |      |      |      |
| **Financing Receivable, Allowance for Credit Loss [Line Items]**                                                |           |      |     |      |      |      |
| Individually evaluated for impairment                                                                           | 11,448         |      | 6,986    |      |      |      |
| Commercial Real Estate | Residential                                                                            |           |      |     |      |      |      |
| **Financing Receivable, Allowance for Credit Loss [Line Items]**                                                |           |      |     |      |      |      |
| Individually evaluated for impairment                                                                           | 0              |      | 0        |      |      |      |
| Commercial Real Estate | Home equity                                                                            |           |      |     |      |      |      |
| **Financing Receivable, Allowance for Credit Loss [Line Items]**                                                |           |      |     |      |      |      |
| Individually evaluated for impairment                                                                           | 0              |      | 0        |      |      |      |
| Residential Real Estate                                                                                         |           |      |     |      |      |      |
| **Financing Receivable, Allowance for Credit Loss [Line Items]**                                                |           |      |     |      |      |      |
| Individually evaluated for impairment                                                                           | 1,849          |      | 2,681    |      |      |      |
| Residential Real Estate | Commercial and industrial loans                                                       |           |      |     |      |      |      |
| **Financing Receivable, Allowance for Credit Loss [Line Items]**                                                |           |      |     |      |      |      |
| Individually evaluated for impairment                                                                           | 0              |      | 0        |      |      |      |
| Residential Real Estate | Construction                                                                          |           |      |     |      |      |      |
| **Financing Receivable, Allowance for Credit Loss [Line Items]**                                                |           |      |     |      |      |      |
| Individually evaluated for impairment                                                                           | 9              |      | 10       |      |      |      |
| Residential Real Estate | Commercial real estate, non-owner occupied                                            |           |      |     |      |      |      |
| **Financing Receivable, Allowance for Credit Loss [Line Items]**                                                |           |      |     |      |      |      |
| Individually evaluated for impairment                                                                           | 0              |      | 0        |      |      |      |
| Residential Real Estate | Commercial real estate, owner occupied                                                |           |      |     |      |      |      |
| **Financing Receivable, Allowance for Credit Loss [Line Items]**                                                |           |      |     |      |      |      |
| Individually evaluated for impairment                                                                           | 0              |      | 0        |      |      |      |
| Residential Real Estate | Residential                                                                           |           |      |     |      |      |      |
| **Financing Receivable, Allowance for Credit Loss [Line Items]**                                                |           |      |     |      |      |      |
| Individually evaluated for impairment                                                                           | 1,562          |      | 2,382    |      |      |      |
| Residential Real Estate | Home equity                                                                           |           |      |     |      |      |      |
| **Financing Receivable, Allowance for Credit Loss [Line Items]**                                                |           |      |     |      |      |      |
| Individually evaluated for impairment                                                                           | 278            |      | 289      |      |      |      |
| Other                                                                                                           |           |      |     |      |      |      |
| **Financing Receivable, Allowance for Credit Loss [Line Items]**                                                |           |      |     |      |      |      |
| Individually evaluated for impairment                                                                           | 51,674         |      | 42,101   |      |      |      |
| Other | Commercial and industrial loans                                                                         |           |      |     |      |      |      |
| **Financing Receivable, Allowance for Credit Loss [Line Items]**                                                |           |      |     |      |      |      |
| Individually evaluated for impairment                                                                           | 51,674         |      | 42,101   |      |      |      |
| Other | Construction                                                                                            |           |      |     |      |      |      |
| **Financing Receivable, Allowance for Credit Loss [Line Items]**                                                |           |      |     |      |      |      |
| Individually evaluated for impairment                                                                           | 0              |      | 0        |      |      |      |
| Other | Commercial real estate, non-owner occupied                                                              |           |      |     |      |      |      |
| **Financing Receivable, Allowance for Credit Loss [Line Items]**                                                |           |      |     |      |      |      |
| Individually evaluated for impairment                                                                           | 0              |      | 0        |      |      |      |
| Other | Commercial real estate, owner occupied                                                                  |           |      |     |      |      |      |
| **Financing Receivable, Allowance for Credit Loss [Line Items]**                                                |           |      |     |      |      |      |
| Individually evaluated for impairment                                                                           | 0              |      | 0        |      |      |      |
| Other | Residential                                                                                             |           |      |     |      |      |      |
| **Financing Receivable, Allowance for Credit Loss [Line Items]**                                                |           |      |     |      |      |      |
| Individually evaluated for impairment                                                                           | 0              |      | 0        |      |      |      |
| Other | Home equity                                                                                             |           |      |     |      |      |      |
| **Financing Receivable, Allowance for Credit Loss [Line Items]**                                                |           |      |     |      |      |      |
| Individually evaluated for impairment                                                                           | 0              |      | 0        |      |      |      |
| Allowance on Collateral Dependent Loans                                                                         |           |      |     |      |      |      |
| **Financing Receivable, Allowance for Credit Loss [Line Items]**                                                |           |      |     |      |      |      |
| Allowance on Collateral Dependent Loans                                                                         | 20,068         |      | 11,512   |      |      |      |
| Allowance on Collateral Dependent Loans | Commercial and industrial loans                                       |           |      |     |      |      |      |
| **Financing Receivable, Allowance for Credit Loss [Line Items]**                                                |           |      |     |      |      |      |
| Increase (decrease) in individually evaluated for impairment                                                    | 9,600          |      |     |      |      |      |
| Net recoveries                                                                                                  | 10,900         |      |     |      |      |      |
| Allowance on Collateral Dependent Loans                                                                         | 19,282         |      | 8,367    |      |      |      |
| Allowance on Collateral Dependent Loans | Construction                                                          |           |      |     |      |      |      |
| **Financing Receivable, Allowance for Credit Loss [Line Items]**                                                |           |      |     |      |      |      |
| Allowance on Collateral Dependent Loans                                                                         | 1              |      | 1        |      |      |      |
| Allowance on Collateral Dependent Loans | Commercial real estate, non-owner occupied                            |           |      |     |      |      |      |
| **Financing Receivable, Allowance for Credit Loss [Line Items]**                                                |           |      |     |      |      |      |
| Increase (decrease) in individually evaluated for impairment                                                    | 8,000          |      |     |      |      |      |
| Net recoveries                                                                                                  | 1,900          |      |     |      |      |      |
| Allowance on Collateral Dependent Loans                                                                         | 160            |      | 2,064    |      |      |      |
| Allowance on Collateral Dependent Loans | Commercial real estate, owner occupied                                |           |      |     |      |      |      |
| **Financing Receivable, Allowance for Credit Loss [Line Items]**                                                |           |      |     |      |      |      |
| Increase (decrease) in individually evaluated for impairment                                                    | 4,500          |      |     |      |      |      |
| Allowance on Collateral Dependent Loans                                                                         | 337            |      | 776      |      |      |      |
| Allowance on Collateral Dependent Loans | Residential                                                           |           |      |     |      |      |      |
| **Financing Receivable, Allowance for Credit Loss [Line Items]**                                                |           |      |     |      |      |      |
| Allowance on Collateral Dependent Loans                                                                         | 247            |      | 260      |      |      |      |
| Allowance on Collateral Dependent Loans | Home equity                                                           |           |      |     |      |      |      |
| **Financing Receivable, Allowance for Credit Loss [Line Items]**                                                |           |      |     |      |      |      |
| Allowance on Collateral Dependent Loans                                                                         | $ 41           |      | $ 44     |      |      |      |

| X                                                                                                                                                                                                                                                                                                                                              |
|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Financing Receivable, Increase (Decrease) Allowance for Credit Loss, Recovery. Net
+ References
No definition available.
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| X                                                                                                                                                                                                                                                                                                                                           |
|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Financing Receivable, Increase (Decrease) Individually Evaluated for Impairment
+ References
No definition available.
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               |
|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - 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
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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
Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 326 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 13 -Publisher FASB -URI https://asc.fasb.org//1943274/2147479319/326-20-50-13Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Name Regulation S-K (SK) -Number 229 -Section 1405 -Paragraph c -Publisher SEC
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                             |
|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
The balance of financing receivables that were individually evaluated for impairment.
+ References
Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 310 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 11C -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org//1943274/2147481962/310-10-50-11CReference 2: http://www.xbrl.org/2003/role/exampleRef -Topic 310 -SubTopic 10 -Name Accounting Standards Codification -Section S99 -Paragraph 4 -Subparagraph (SAB Topic 6.L(5)(a)) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480418/310-10-S99-4
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| X                                                                                                                                                                                                             |
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|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
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| X                                                                                                                                                 |
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| X                                                                                                                                              |
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