| **Disclosures About Fair Value of Assets and Liabilities - Unobservable Inputs Used in Recurring and Nonrecurring Level 3 Fair Value Measurements Other Than Goodwill (Details) - Significant Unobservable Inputs (Level 3) $ in Thousands** | 9 Months Ended | 12 Months Ended |
|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|----------------|-----------------|
||
| State and municipal securities | Discounted cash flow                                                                                                                                                                                        |           |            |
| **Fair Value Measurement Inputs and Valuation Techniques [Line Items]**                                                                                                                                                                      |           |            |
| Fair Value                                                                                                                                                                                                                                   | $ 3,280        | $ 3,943         |
| State and municipal securities | Discounted cash flow | Minimum                                                                                                                                                                              |           |            |
| **Fair Value Measurement Inputs and Valuation Techniques [Line Items]**                                                                                                                                                                      |           |            |
| Maturity/Call date                                                                                                                                                                                                                           | 1 month        | 1 month         |
| US Muni BQ curve                                                                                                                                                                                                                             | A-             | A-              |
| State and municipal securities | Discounted cash flow | Maximum                                                                                                                                                                              |           |            |
| **Fair Value Measurement Inputs and Valuation Techniques [Line Items]**                                                                                                                                                                      |           |            |
| Maturity/Call date                                                                                                                                                                                                                           | 20 years       | 20 years        |
| US Muni BQ curve                                                                                                                                                                                                                             | BBB-           | BBB-            |
| Corporate obligations and U.S. Government-sponsored mortgage backed securities | Discounted cash flow                                                                                                                                        |           |            |
| **Fair Value Measurement Inputs and Valuation Techniques [Line Items]**                                                                                                                                                                      |           |            |
| Fair Value                                                                                                                                                                                                                                   | $ 35           |            |
| Corporate obligations and equity securities | Discounted cash flow                                                                                                                                                                           |           |            |
| **Fair Value Measurement Inputs and Valuation Techniques [Line Items]**                                                                                                                                                                      |           |            |
| Fair Value                                                                                                                                                                                                                                   |           | $ 35            |
| Impaired loans (collateral dependent) | Collateral based measurements                                                                                                                                                                        |           |            |
| **Fair Value Measurement Inputs and Valuation Techniques [Line Items]**                                                                                                                                                                      |           |            |
| Fair Value                                                                                                                                                                                                                                   | 5,344          | 9,576           |
| Other real estate owned | Appraisals                                                                                                                                                                                                         |           |            |
| **Fair Value Measurement Inputs and Valuation Techniques [Line Items]**                                                                                                                                                                      |           |            |
| Fair Value                                                                                                                                                                                                                                   | $ 937          | $ 859           |
| Discount rate | State and municipal securities | Discounted cash flow | Minimum                                                                                                                                                              |           |            |
| **Fair Value Measurement Inputs and Valuation Techniques [Line Items]**                                                                                                                                                                      |           |            |
| Debt Securities, Available-for-sale, Measurement Input                                                                                                                                                                                       | 0.01           | 0.0069          |
| Discount rate | State and municipal securities | Discounted cash flow | Maximum                                                                                                                                                              |           |            |
| **Fair Value Measurement Inputs and Valuation Techniques [Line Items]**                                                                                                                                                                      |           |            |
| Debt Securities, Available-for-sale, Measurement Input                                                                                                                                                                                       | 0.05           | 0.05            |
| Risk free rate | Corporate obligations and U.S. Government-sponsored mortgage backed securities | Discounted cash flow                                                                                                                       |           |            |
| **Fair Value Measurement Inputs and Valuation Techniques [Line Items]**                                                                                                                                                                      |           |            |
| Rate basis                                                                                                                                                                                                                                   | 3 month LIBOR  |            |
| Risk free rate | Corporate obligations and equity securities | Discounted cash flow                                                                                                                                                          |           |            |
| **Fair Value Measurement Inputs and Valuation Techniques [Line Items]**                                                                                                                                                                      |           |            |
| Rate basis                                                                                                                                                                                                                                   |           | 3 month LIBOR   |
| Discount to reflect current market conditions | Corporate obligations and U.S. Government-sponsored mortgage backed securities | Discounted cash flow                                                                                        |           |            |
| **Fair Value Measurement Inputs and Valuation Techniques [Line Items]**                                                                                                                                                                      |           |            |
| Debt Securities, Available-for-sale, Measurement Input                                                                                                                                                                                       | 0.0200         |            |
| Discount to reflect current market conditions | Corporate obligations and equity securities | Discounted cash flow                                                                                                                           |           |            |
| **Fair Value Measurement Inputs and Valuation Techniques [Line Items]**                                                                                                                                                                      |           |            |
| Debt Securities, Available-for-sale, Measurement Input                                                                                                                                                                                       |           | 0.0200          |
| Discount to reflect current market conditions | Impaired loans (collateral dependent) | Collateral based measurements | Minimum                                                                                                              |           |            |
| **Fair Value Measurement Inputs and Valuation Techniques [Line Items]**                                                                                                                                                                      |           |            |
| Debt Securities, Available-for-sale, Measurement Input                                                                                                                                                                                       | 0.00           | 0.00            |
| Discount to reflect current market conditions | Impaired loans (collateral dependent) | Collateral based measurements | Maximum                                                                                                              |           |            |
| **Fair Value Measurement Inputs and Valuation Techniques [Line Items]**                                                                                                                                                                      |           |            |
| Debt Securities, Available-for-sale, Measurement Input                                                                                                                                                                                       | 0.10           | 0.10            |
| Discount to reflect current market conditions | Impaired loans (collateral dependent) | Collateral based measurements | Weighted Average                                                                                                     |           |            |
| **Fair Value Measurement Inputs and Valuation Techniques [Line Items]**                                                                                                                                                                      |           |            |
| Debt Securities, Available-for-sale, Measurement Input                                                                                                                                                                                       | 0.02           | 0.01            |
| Discount to reflect current market conditions | Other real estate owned | Appraisals | Minimum                                                                                                                                               |           |            |
| **Fair Value Measurement Inputs and Valuation Techniques [Line Items]**                                                                                                                                                                      |           |            |
| Other real estate owned                                                                                                                                                                                                                      | 0.00           | 0.00            |
| Discount to reflect current market conditions | Other real estate owned | Appraisals | Maximum                                                                                                                                               |           |            |
| **Fair Value Measurement Inputs and Valuation Techniques [Line Items]**                                                                                                                                                                      |           |            |
| Other real estate owned                                                                                                                                                                                                                      | 0.24           | 0.10            |
| Discount to reflect current market conditions | Other real estate owned | Appraisals | Weighted Average                                                                                                                                      |           |            |
| **Fair Value Measurement Inputs and Valuation Techniques [Line Items]**                                                                                                                                                                      |           |            |
| Other real estate owned                                                                                                                                                                                                                      | 0.03           | 0.02            |

| X                                                                                                                                                                                                                                                                 |
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| - Definition
Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.
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| - Definition
Description of the credit rating indicative of likelihood of repayment of the debt instrument given by a credit rating agency (for example, Standard and Poor's, Moody's, Fitch).
+ References
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| - Definition
Value of input used to measure investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).
+ References
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| - 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.
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| - Definition
Value of input used to measure real estate owned by financial institution by financial institution which is not directly related to its business.
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