| **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                                                                                                              | $ 205          | $ 200          | $ 606 | $ 1,088 |
| Term Modification                                                                                                         |           |           |   |   |
| **Financing Receivable, Modifications [Line Items]**                                                                      |           |           |   |   |
| Modification                                                                                                              |                | 5              | 77 | 46 |
| Rate Modification                                                                                                         |           |           |   |   |
| **Financing Receivable, Modifications [Line Items]**                                                                      |           |           |   |   |
| Modification                                                                                                              | 112            | 195            | 290 | 600 |
| Combination                                                                                                               |           |           |   |   |
| **Financing Receivable, Modifications [Line Items]**                                                                      |           |           |   |   |
| Modification                                                                                                              | 93             |                | 239 | 442 |
| Commercial and industrial loans                                                                                           |           |           |   |   |
| **Financing Receivable, Modifications [Line Items]**                                                                      |           |           |   |   |
| Modification                                                                                                              |           | 5              |   | 173 |
| Commercial and industrial loans | Term Modification                                                                       |           |           |   |   |
| **Financing Receivable, Modifications [Line Items]**                                                                      |           |           |   |   |
| Modification                                                                                                              |           | 5              |   | 5 |
| Commercial and industrial loans | Rate Modification                                                                       |           |           |   |   |
| **Financing Receivable, Modifications [Line Items]**                                                                      |           |           |   |   |
| Modification                                                                                                              |           |                |   |  |
| Commercial and industrial loans | Combination                                                                             |           |           |   |   |
| **Financing Receivable, Modifications [Line Items]**                                                                      |           |           |   |   |
| Modification                                                                                                              |           |                |   | 168 |
| Commercial and farmland                                                                                                   |           |           |   |   |
| **Financing Receivable, Modifications [Line Items]**                                                                      |           |           |   |   |
| Modification                                                                                                              |           |           |   | 334 |
| Commercial and farmland | Term Modification                                                                               |           |           |   |   |
| **Financing Receivable, Modifications [Line Items]**                                                                      |           |           |   |   |
| Modification                                                                                                              |           |           |   | 41 |
| Commercial and farmland | Rate Modification                                                                               |           |           |   |   |
| **Financing Receivable, Modifications [Line Items]**                                                                      |           |           |   |   |
| Modification                                                                                                              |           |           |   | 61 |
| Commercial and farmland | Combination                                                                                     |           |           |   |   |
| **Financing Receivable, Modifications [Line Items]**                                                                      |           |           |   |   |
| Modification                                                                                                              |           |           |   | 232 |
| Residential                                                                                                               |           |           |   |   |
| **Financing Receivable, Modifications [Line Items]**                                                                      |           |           |   |   |
| Modification                                                                                                              | 140            | 122            | 447 | 508 |
| Residential | Term Modification                                                                                           |           |           |   |   |
| **Financing Receivable, Modifications [Line Items]**                                                                      |           |           |   |   |
| Modification                                                                                                              |                |                |  |  |
| Residential | Rate Modification                                                                                           |           |           |   |   |
| **Financing Receivable, Modifications [Line Items]**                                                                      |           |           |   |   |
| Modification                                                                                                              | 47             | 122            | 208 | 466 |
| Residential | Combination                                                                                                 |           |           |   |   |
| **Financing Receivable, Modifications [Line Items]**                                                                      |           |           |   |   |
| Modification                                                                                                              | 93             |                | 239 | 42 |
| Home equity                                                                                                               |           |           |   |   |
| **Financing Receivable, Modifications [Line Items]**                                                                      |           |           |   |   |
| Modification                                                                                                              | 65             | 73             | 153 | 73 |
| Home equity | Term Modification                                                                                           |           |           |   |   |
| **Financing Receivable, Modifications [Line Items]**                                                                      |           |           |   |   |
| Modification                                                                                                              |                |                | 77 |  |
| Home equity | Rate Modification                                                                                           |           |           |   |   |
| **Financing Receivable, Modifications [Line Items]**                                                                      |           |           |   |   |
| Modification                                                                                                              | 65             | 73             | 76 | 73 |
| Home equity | Combination                                                                                                 |           |           |   |   |
| **Financing Receivable, Modifications [Line Items]**                                                                      |           |           |   |   |
| Modification                                                                                                              |                |                |  |  |
| Individuals' loans for household and other personal expenditures                                                          |           |           |   |   |
| **Financing Receivable, Modifications [Line Items]**                                                                      |           |           |   |   |
| Modification                                                                                                              |           |           | 6 |   |
| Individuals' loans for household and other personal expenditures | Rate Modification                                      |           |           |   |   |
| **Financing Receivable, Modifications [Line Items]**                                                                      |           |           |   |   |
| Modification                                                                                                              |           |           | 6 |   |
| Individuals' loans for household and other personal expenditures | 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.
+ Details**Name:**us-gaap_FinancingReceivableModificationsLineItems**Namespace Prefix:**us-gaap_**Data Type:**xbrli:stringItemType**Balance Type:**na**Period Type:**duration |
| X                                                                                                                                                                                                  |
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| X                                                                                                                                                                                                             |
|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
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| X                                                                                                                                                                                                           |
|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
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| X                                                                                                                                                                                                         |
|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
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| X                                                                                                                                                                                              |
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| X                                                                                                                                                                                                |
|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
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