| **Loans and Allowance - Narrative (Details) - USD ($) $ in Thousands** | 3 Months Ended | 12 Months Ended |        |
|------------------------------------------------------------------------|----------------|-----------------|--------|
||
| **Accounts, Notes, Loans and Financing Receivable [Line Items]**       |           |            |   |   |   |   |   |   |   |   |   |   |
| Loans held for sale                                                    | $ 2,929        |            |   |   | $ 9,894 |   |   |   | $ 2,929 | $ 9,894 |   |   |
| Allowance for loan losses                                              | 66,037         |            |   |   | 62,453 |   |   |   | 66,037 | 62,453 | $ 63,964 | $ 67,870 |
| Increase in allowance for loan losses                                  |           |            |   |   |   |   |   |   | 3,584 |   |   |   |
| Net charge offs                                                        |           |            |   |   |   |   |   |   | 2,073 |   |   |   |
| Increase in net charge offs                                            |           |            |   |   |   |   |   |   | 145 |   |   |   |
| Provision for loan losses                                              | 2,417          | $ 1,900         | $ 790  | $ 550 |  |  | $ 417 |  | 5,657 | 417 | 2,560 |   |
| Increase in provision for loan losses                                  |           |            |   |   |   |   |   |   | 5,240 |   |   |   |
| Commercial impaired loan total                                         | 72,050         |            |   |   | 97,527 |   |   |   | $ 72,050 | 97,527 | 116,223 |   |
| Merger with Ameriana Bancorp                                           |           |            |   |   |   |   |   |   |   |   |   |   |
| **Accounts, Notes, Loans and Financing Receivable [Line Items]**       |           |            |   |   |   |   |   |   |   |   |   |   |
| Commercial impaired loan total                                         |           |            |   |   | 11,365 |   |   |   |   | 11,365 |   |   |
| Merger with C Financial Corporation                                    |           |            |   |   |   |   |   |   |   |   |   |   |
| **Accounts, Notes, Loans and Financing Receivable [Line Items]**       |           |            |   |   |   |   |   |   |   |   |   |   |
| Commercial impaired loan total                                         |           |            |   |   | 1,841 |   |   |   |   | 1,841 |   |   |
| Merger with Community Bancshares, Inc.                                 |           |            |   |   |   |   |   |   |   |   |   |   |
| **Accounts, Notes, Loans and Financing Receivable [Line Items]**       |           |            |   |   |   |   |   |   |   |   |   |   |
| Commercial impaired loan total                                         |           |            |   |   |   |   |   |   |   |   | 17,027 |   |
| Commercial and farmland                                                |           |            |   |   |   |   |   |   |   |   |   |   |
| **Accounts, Notes, Loans and Financing Receivable [Line Items]**       |           |            |   |   |   |   |   |   |   |   |   |   |
| Percentage of troubled debt restructured loans                         |           |            |   |   |   |   |   |   | 56.00% |   |   |   |
| Residential                                                            |           |            |   |   |   |   |   |   |   |   |   |   |
| **Accounts, Notes, Loans and Financing Receivable [Line Items]**       |           |            |   |   |   |   |   |   |   |   |   |   |
| Allowance for loan losses                                              | 11,755         |            |   |   | 11,139 |   |   |   | $ 11,755 | 11,139 | 13,152 | 15,077 |
| Provision for loan losses                                              |           |            |   |   |   |   |   |   | 1,515 | 310 | (839) |   |
| Consumer                                                               |           |            |   |   |   |   |   |   |   |   |   |   |
| **Accounts, Notes, Loans and Financing Receivable [Line Items]**       |           |            |   |   |   |   |   |   |   |   |   |   |
| Allowance for loan losses                                              | 2,923          |            |   |   | 2,689 |   |   |   | 2,923 | 2,689 | 2,658 | $ 2,515 |
| Provision for loan losses                                              |           |            |   |   |   |   |   |   | 432 | 299 | $ 423 |   |
| Mortgage loans for which formal foreclosure proceedings are in process | $ 1,530        |            |   |   | $ 1,391 |   |   |   | $ 1,530 | $ 1,391 |   |   |

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|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
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Financing Receivable, Modifications, Post-Modification, Loans as Percentage of Troubled Debt Restructured Loans
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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
Amount of increase (decrease) of allowance reserve for credit loss.
+ References
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| X                                                                                                                                                                                                                                                                                                                |
|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
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Amount, after recoveries, of loans and leases that have been written-off.
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|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount of investment of impaired financing receivables with related allowance for credit losses and without a related allowance for credit losses.
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|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount of allowance to cover probable credit losses on loans and leases. Includes carryover of or adjustments to the allowance for loan losses in connection with business combinations. Excludes allowance for loans and leases covered under loss sharing agreements.
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                             |
|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
The face amount of loans that will be sold to other entities.
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               |
|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Recorded investment of consumer mortgage loan receivables secured by residential real estate properties for which formal foreclosure proceedings are in process.
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|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount of expense related loan transactions, lease transactions, credit loss from transactions other than loan and lease transactions, and other loss based on assessment of uncollectability from the counterparty to reduce the account to their net realizable value.
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