| **Loans and Allowance - Summary of Troubled Debt Restructurings (Details) (USD $)In Thousands, unless otherwise specified** | 3 Months Ended | 9 Months Ended |
|-----------------------------------------------------------------------------------------------------------------------------|----------------|----------------|
||
| **Financing Receivable, Modifications [Line Items]**                                                                        |           |           |   |   |
| Pre-Modification Recorded Balance                                                                                           | $ 1,816        | $ 2,382        | $ 7,445 | $ 7,202 |
| Post-Modification Recorded Balance                                                                                          | 1,843          | 2,584          | 6,459 | 6,988 |
| Number of Loans                                                                                                             | 9              | 14             | 25 | 38 |
| Commercial and industrial loans                                                                                             |           |           |   |   |
| **Financing Receivable, Modifications [Line Items]**                                                                        |           |           |   |   |
| Pre-Modification Recorded Balance                                                                                           | 162            | 875            | 294 | 1,155 |
| Post-Modification Recorded Balance                                                                                          | 183            | 1,048          | 315 | 1,327 |
| Number of Loans                                                                                                             | 1              | 3              | 5 | 6 |
| Real estate loans - Construction                                                                                            |           |           |   |   |
| **Financing Receivable, Modifications [Line Items]**                                                                        |           |           |   |   |
| Pre-Modification Recorded Balance                                                                                           |           | 303            |   | 794 |
| Post-Modification Recorded Balance                                                                                          |           | 303            |   | 653 |
| Number of Loans                                                                                                             |           | 1              |   | 2 |
| Real estate loans - Commercial and farm land                                                                                |           |           |   |   |
| **Financing Receivable, Modifications [Line Items]**                                                                        |           |           |   |   |
| Pre-Modification Recorded Balance                                                                                           | 1,464          | 875            | 6,449 | 2,967 |
| Post-Modification Recorded Balance                                                                                          | 1,469          | 875            | 5,450 | 2,828 |
| Number of Loans                                                                                                             | 6              | 2              | 10 | 7 |
| Real estate loans - Residential                                                                                             |           |           |   |   |
| **Financing Receivable, Modifications [Line Items]**                                                                        |           |           |   |   |
| Pre-Modification Recorded Balance                                                                                           | 190            | 239            | 658 | 2,196 |
| Post-Modification Recorded Balance                                                                                          | 191            | 241            | 649 | 2,063 |
| Number of Loans                                                                                                             | 2              | 4              | 8 | 19 |
| Individuals' loans for household and other personal expenditures                                                            |           |           |   |   |
| **Financing Receivable, Modifications [Line Items]**                                                                        |           |           |   |   |
| Pre-Modification Recorded Balance                                                                                           |      | 90             | 44 | 90 |
| Post-Modification Recorded Balance                                                                                          |      | $ 117          | $ 45 | $ 117 |
| Number of Loans                                                                                                             |      | 4              | 2 | 4 |

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