| **Loans and Allowance - Summary of Troubled Debt Restructurings (Details) $ in Thousands** | 3 Months Ended | 6 Months Ended |
|--------------------------------------------------------------------------------------------|----------------|----------------|
||
| **Financing Receivable, Modifications [Line Items]**                                       |           |           |   |   |
| Pre-Modification Recorded Balance                                                          | $ 4,854        | $ 1,943        | $ 6,044 | $ 4,408 |
| Post-Modification Recorded Balance                                                         | $ 4,795        | $ 1,944        | $ 5,871 | $ 5,152 |
| Number of Loans | loan                                                                     | 9              | 4              | 18 | 11 |
| Commercial and industrial loans                                                            |           |           |   |   |
| **Financing Receivable, Modifications [Line Items]**                                       |           |           |   |   |
| Pre-Modification Recorded Balance                                                          |                | $ 1,386        | $ 260 | $ 3,748 |
| Post-Modification Recorded Balance                                                         |                | $ 536          | $ 260 | $ 1,897 |
| Number of Loans | loan                                                                     |                | 1              | 3 | 5 |
| Agricultural production financing and other loans to farmers                               |           |           |   |   |
| **Financing Receivable, Modifications [Line Items]**                                       |           |           |   |   |
| Pre-Modification Recorded Balance                                                          | $ 1,141        |           | $ 1,606 |   |
| Post-Modification Recorded Balance                                                         | $ 1,141        |           | $ 1,472 |   |
| Number of Loans | loan                                                                     | 3              |           | 5 |   |
| 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                                                          | $ 3,539        | $ 537          | $ 3,891 | $ 537 |
| Post-Modification Recorded Balance                                                         | $ 3,508        | $ 537          | $ 3,860 | $ 2,280 |
| Number of Loans | loan                                                                     | 5              | 1              | 6 | 2 |
| Real estate loans - Residential                                                            |           |           |   |   |
| **Financing Receivable, Modifications [Line Items]**                                       |           |           |   |   |
| Pre-Modification Recorded Balance                                                          |                | $ 20           | $ 113 | $ 44 |
| Post-Modification Recorded Balance                                                         |                | $ 871          | $ 133 | $ 895 |
| Number of Loans | loan                                                                     |                | 2              | 3 | 3 |
| Real estate loans - Home Equity                                                            |           |           |   |   |
| **Financing Receivable, Modifications [Line Items]**                                       |           |           |   |   |
| Pre-Modification Recorded Balance                                                          | $ 174          |           | $ 174 |   |
| Post-Modification Recorded Balance                                                         | $ 146          |           | $ 146 |   |
| Number of Loans | loan                                                                     | 1              |           | 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=66008989&loc=SL6953676-111524
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|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - 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=66008989&loc=SL6953676-111524
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|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - 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=66008989&loc=SL6953676-111524
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