| **Loans and Allowance - Summary of Troubled Debt Restructurings (Details) $ in Thousands** | 3 Months Ended | 9 Months Ended |
|--------------------------------------------------------------------------------------------|----------------|----------------|
||
| **Financing Receivable, Modifications [Line Items]**                                       |           |           |   |   |
| Pre-Modification Recorded Balance                                                          | $ 1,357        | $ 485          | $ 5,765 | $ 1,047 |
| Post-Modification Recorded Balance                                                         | $ 1,217        | $ 492          | $ 6,370 | $ 1,056 |
| Number of Loans | loan                                                                     | 5              | 12             | 16 | 20 |
| Commercial and industrial loans                                                            |           |           |   |   |
| **Financing Receivable, Modifications [Line Items]**                                       |           |           |   |   |
| Pre-Modification Recorded Balance                                                          | $ 363          |           | $ 4,111 |   |
| Post-Modification Recorded Balance                                                         | $ 218          |           | $ 2,115 |   |
| Number of Loans | loan                                                                     | 2              |           | 7 |   |
| 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                                                          | $ 744          |                | $ 1,281 | $ 259 |
| Post-Modification Recorded Balance                                                         | $ 744          |                | $ 3,025 | $ 259 |
| Number of Loans | loan                                                                     | 1              |                | 3 | 1 |
| Real estate loans - Residential                                                            |           |           |   |   |
| **Financing Receivable, Modifications [Line Items]**                                       |           |           |   |   |
| Pre-Modification Recorded Balance                                                          | $ 11           | $ 256          | $ 55 | $ 448 |
| Post-Modification Recorded Balance                                                         | $ 13           | $ 245          | $ 908 | $ 428 |
| Number of Loans | loan                                                                     | 1              | 5              | 4 | 7 |
| Real estate loans - Home Equity                                                            |           |           |   |   |
| **Financing Receivable, Modifications [Line Items]**                                       |           |           |   |   |
| Pre-Modification Recorded Balance                                                          | $ 239          | $ 229          | $ 239 | $ 314 |
| Post-Modification Recorded Balance                                                         | $ 242          | $ 247          | $ 242 | $ 343 |
| Number of Loans | loan                                                                     | 1              | 7              | 1 | 10 |
| Individuals' loans for household and other personal expenditures                           |           |           |   |   |
| **Financing Receivable, Modifications [Line Items]**                                       |           |           |   |   |
| Pre-Modification Recorded Balance                                                          |           |                |   | $ 26 |
| Post-Modification Recorded Balance                                                         |           |                |   | $ 26 |
| Number of Loans | loan                                                                     |           |                |   | 2 |

| 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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|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - 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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