| **Loans and Allowance - Summary of Troubled Debt Restructurings by Modification Type (Details) - USD ($) $ in Thousands** | 3 Months Ended | 9 Months Ended |
|---------------------------------------------------------------------------------------------------------------------------|----------------|----------------|
||
| **Financing Receivable, Modifications [Line Items]**                                                                      |           |           |   |   |
| Modification                                                                                                              | $ 814          | $ 1,212        | $ 5,968 | $ 5,378 |
| Term Modification                                                                                                         |           |           |   |   |
| **Financing Receivable, Modifications [Line Items]**                                                                      |           |           |   |   |
| Modification                                                                                                              |                | 138            | 1,314 | 2,993 |
| Rate Modification                                                                                                         |           |           |   |   |
| **Financing Receivable, Modifications [Line Items]**                                                                      |           |           |   |   |
| Modification                                                                                                              | 719            | 255            | 970 | 301 |
| Combination                                                                                                               |           |           |   |   |
| **Financing Receivable, Modifications [Line Items]**                                                                      |           |           |   |   |
| Modification                                                                                                              | 95             | 819            | 3,684 | 2,084 |
| Commercial and industrial loans                                                                                           |           |           |   |   |
| **Financing Receivable, Modifications [Line Items]**                                                                      |           |           |   |   |
| Modification                                                                                                              |           | 213            | 197 | 1,886 |
| Commercial and industrial loans | Term Modification                                                                       |           |           |   |   |
| **Financing Receivable, Modifications [Line Items]**                                                                      |           |           |   |   |
| Modification                                                                                                              |           | 138            |  | 806 |
| Commercial and industrial loans | Rate Modification                                                                       |           |           |   |   |
| **Financing Receivable, Modifications [Line Items]**                                                                      |           |           |   |   |
| Modification                                                                                                              |           |                |  |  |
| Commercial and industrial loans | Combination                                                                             |           |           |   |   |
| **Financing Receivable, Modifications [Line Items]**                                                                      |           |           |   |   |
| Modification                                                                                                              |           | 75             | 197 | 1,080 |
| Agricultural production financing and other loans to farmers                                                              |           |           |   |   |
| **Financing Receivable, Modifications [Line Items]**                                                                      |           |           |   |   |
| Modification                                                                                                              |           |           | 898 |   |
| Agricultural production financing and other loans to farmers | Term Modification                                          |           |           |   |   |
| **Financing Receivable, Modifications [Line Items]**                                                                      |           |           |   |   |
| Modification                                                                                                              |           |           | 898 |   |
| Agricultural production financing and other loans to farmers | Rate Modification                                          |           |           |   |   |
| **Financing Receivable, Modifications [Line Items]**                                                                      |           |           |   |   |
| Modification                                                                                                              |           |           |  |   |
| Agricultural production financing and other loans to farmers | Combination                                                |           |           |   |   |
| **Financing Receivable, Modifications [Line Items]**                                                                      |           |           |   |   |
| Modification                                                                                                              |           |           |  |   |
| Real estate loans - Commercial and farmland                                                                               |           |           |   |   |
| **Financing Receivable, Modifications [Line Items]**                                                                      |           |           |   |   |
| Modification                                                                                                              | 95             | 744            | 3,903 | 2,341 |
| Real estate loans - Commercial and farmland | Term Modification                                                           |           |           |   |   |
| **Financing Receivable, Modifications [Line Items]**                                                                      |           |           |   |   |
| Modification                                                                                                              |                |                | 416 | 1,337 |
| Real estate loans - Commercial and farmland | Rate Modification                                                           |           |           |   |   |
| **Financing Receivable, Modifications [Line Items]**                                                                      |           |           |   |   |
| Modification                                                                                                              |                |                |  |  |
| Real estate loans - Commercial and farmland | Combination                                                                 |           |           |   |   |
| **Financing Receivable, Modifications [Line Items]**                                                                      |           |           |   |   |
| Modification                                                                                                              | 95             | 744            | 3,487 | 1,004 |
| Real estate loans - Residential                                                                                           |           |           |   |   |
| **Financing Receivable, Modifications [Line Items]**                                                                      |           |           |   |   |
| Modification                                                                                                              | 663            | 13             | 773 | 909 |
| Real estate loans - Residential | Term Modification                                                                       |           |           |   |   |
| **Financing Receivable, Modifications [Line Items]**                                                                      |           |           |   |   |
| Modification                                                                                                              |                |                |  | 850 |
| Real estate loans - Residential | Rate Modification                                                                       |           |           |   |   |
| **Financing Receivable, Modifications [Line Items]**                                                                      |           |           |   |   |
| Modification                                                                                                              | 663            | 13             | 773 | 59 |
| Real estate loans - Residential | Combination                                                                             |           |           |   |   |
| **Financing Receivable, Modifications [Line Items]**                                                                      |           |           |   |   |
| Modification                                                                                                              |                |                |  |  |
| Real estate loans - Home Equity                                                                                           |           |           |   |   |
| **Financing Receivable, Modifications [Line Items]**                                                                      |           |           |   |   |
| Modification                                                                                                              | 56             | 242            | 197 | 242 |
| Real estate loans - Home Equity | Term Modification                                                                       |           |           |   |   |
| **Financing Receivable, Modifications [Line Items]**                                                                      |           |           |   |   |
| Modification                                                                                                              |                |                |  |  |
| Real estate loans - Home Equity | Rate Modification                                                                       |           |           |   |   |
| **Financing Receivable, Modifications [Line Items]**                                                                      |           |           |   |   |
| Modification                                                                                                              | 56             | 242            | 197 | 242 |
| Real estate loans - Home Equity | Combination                                                                             |           |           |   |   |
| **Financing Receivable, Modifications [Line Items]**                                                                      |           |           |   |   |
| Modification                                                                                                              |                |                |  |  |

| X                                                                                                                                                                                                                                                                                                                           |
|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Financing Receivable, Modifications, Recorded Investment During Period
+ References
No definition available.
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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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| X                                                                                                                                                                                                  |
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| X                                                                                                                                                                                                      |
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| X                                                                                                                                                                                                           |
|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
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| X                                                                                                                                                                                                         |
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