| **Loans and Allowance - Summary of Troubled Debt Restructurings (Details) $ in Thousands** | 3 Months Ended |
|--------------------------------------------------------------------------------------------|----------------|
||
| **Financing Receivable, Modifications [Line Items]**                                       |           |   |
| Pre-Modification Recorded Balance                                                          | $ 1,203        | $ 2,465 |
| Post-Modification Recorded Balance                                                         | $ 1,089        | $ 3,208 |
| Number of Loans | loan                                                                     | 10             | 7 |
| Commercial and industrial loans                                                            |           |   |
| **Financing Receivable, Modifications [Line Items]**                                       |           |   |
| Pre-Modification Recorded Balance                                                          | $ 260          | $ 2,362 |
| Post-Modification Recorded Balance                                                         | $ 260          | $ 1,361 |
| Number of Loans | loan                                                                     | 3              | 4 |
| Agricultural production financing and other loans to farmers                               |           |   |
| **Financing Receivable, Modifications [Line Items]**                                       |           |   |
| Pre-Modification Recorded Balance                                                          | $ 465          |   |
| Post-Modification Recorded Balance                                                         | $ 331          |   |
| Number of Loans | loan                                                                     | 2              |   |
| Real estate loans - Construction                                                           |           |   |
| **Financing Receivable, Modifications [Line Items]**                                       |           |   |
| Pre-Modification Recorded Balance                                                          |           | $ 79 |
| Post-Modification Recorded Balance                                                         |           | $ 80 |
| Number of Loans | loan                                                                     |           | 1 |
| Real estate loans - Commercial and farmland                                                |           |   |
| **Financing Receivable, Modifications [Line Items]**                                       |           |   |
| Pre-Modification Recorded Balance                                                          | $ 352          |  |
| Post-Modification Recorded Balance                                                         | $ 352          | $ 1,743 |
| Number of Loans | loan                                                                     | 1              | 1 |
| Real estate loans - Residential                                                            |           |   |
| **Financing Receivable, Modifications [Line Items]**                                       |           |   |
| Pre-Modification Recorded Balance                                                          | $ 113          | $ 24 |
| Post-Modification Recorded Balance                                                         | $ 133          | $ 24 |
| Number of Loans | loan                                                                     | 3              | 1 |
| Individuals' loans for household and other personal expenditures                           |           |   |
| **Financing Receivable, Modifications [Line Items]**                                       |           |   |
| Pre-Modification Recorded Balance                                                          | $ 13           |   |
| Post-Modification Recorded Balance                                                         | $ 13           |   |
| Number of Loans | loan                                                                     | 1              |   |

| 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                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                          |
|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Number of financing receivables that have been modified by troubled debt restructurings.
+ References
Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 33 -URI http://asc.fasb.org/extlink&oid=49124121&loc=SL6953676-111524
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                |
|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Post-modification amount of investment in financing receivables modified by troubled debt restructurings.
+ References
Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 33 -URI http://asc.fasb.org/extlink&oid=49124121&loc=SL6953676-111524
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                              |
|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Pre-modification amount of investment in financing receivables modified by troubled debt restructurings.
+ References
Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 33 -URI http://asc.fasb.org/extlink&oid=49124121&loc=SL6953676-111524
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