| **Core Deposit and Other Intangibles - Narrative (Details) - USD ($)** | 3 Months Ended | 9 Months Ended | 12 Months Ended |           |           |
|------------------------------------------------------------------------|----------------|----------------|-----------------|-----------|-----------|
||
| **Finite-Lived Intangible Assets [Line Items]**                        |           |           |            |      |      |
| Measurement period adjustment                                          |           | $ 2,142,000    |                 |      |      |
| FMIG                                                                   |           |           |            |      |      |
| **Finite-Lived Intangible Assets [Line Items]**                        |           |           |            |      |      |
| Other intangible reduction                                             |           |           |            | $ 742,000 |      |
| Ameriana                                                               |           |           |            |      |      |
| **Finite-Lived Intangible Assets [Line Items]**                        |           |           |            |      |      |
| Core deposit intangible                                                |           |           | $ 5,342,000     |      |      |
| Measurement period adjustment                                          | $ 2,142,000    |           |            |      |      |
| C Financial                                                            |           |           |            |      |      |
| **Finite-Lived Intangible Assets [Line Items]**                        |           |           |            |      |      |
| Core deposit intangible                                                |           |           |            |      | $ 981,000 |

| X                                                                                                                                                                                                                                                                                               |
|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Other Finite-Lived Intangible Assets, Reduction in Value
+ References
No definition available.
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |
|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
The amount of identifiable intangible assets recognized as of the acquisition date.
+ References
Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 10 -Section 55 -Paragraph 37 -URI http://asc.fasb.org/extlink&oid=73531372&loc=d3e2207-128464Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=73530397&loc=d3e4845-128472
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| 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.
+ Details**Name:**us-gaap_FiniteLivedIntangibleAssetsLineItems**Namespace Prefix:**us-gaap_**Data Type:**xbrli:stringItemType**Balance Type:**na**Period Type:**duration |
| X                                                                                                                                                                                                                                                                                                                                                                                                                         |
|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount of increase (decrease) to assets, excluding financial assets and goodwill, lacking physical substance with a finite life for purchase accounting adjustments.
+ References
No definition available.
+ Details**Name:**us-gaap_FiniteLivedIntangibleAssetsPurchaseAccountingAdjustments**Namespace Prefix:**us-gaap_**Data Type:**xbrli:monetaryItemType**Balance Type:**debit**Period Type:**duration |
| X                                                                                                                                                                                                                      |
|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
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| X                                                                                                                                                  |
|----------------------------------------------------------------------------------------------------------------------------------------------------|
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| X                                                                                                                                                                  |
|--------------------------------------------------------------------------------------------------------------------------------------------------------------------|
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