| **Accounting for Certain Loans Acquired in a Purchase - Accretable Yield or Income Expected to be Collected (Details) - USD ($) $ in Thousands** | 3 Months Ended | 6 Months Ended |
|--------------------------------------------------------------------------------------------------------------------------------------------------|----------------|----------------|
||
| **Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Accretable Yield Movement Schedule [Roll Forward]**                   |           |           |   |   |
| Beginning balance                                                                                                                                | $ 4,817        | $ 5,336        | $ 5,390 | $ 5,552 |
| Additions                                                                                                                                        | 145            |           | 145 |   |
| Accretion                                                                                                                                        | (1,247)        | $ (1,457)      | (2,952) | $ (1,945) |
| Reclassification from nonaccretable                                                                                                              | 734            | $ 779          | 1,866 | 1,086 |
| Disposals                                                                                                                                        | (8)            |           | (8) | (35) |
| Ending balance                                                                                                                                   | $ 4,441        | $ 4,658        | $ 4,441 | 4,658 |
| Merger with C Financial Corporation                                                                                                              |           |           |   |   |
| **Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Accretable Yield Movement Schedule [Roll Forward]**                   |           |           |   |   |
| Beginning balance                                                                                                                                |           |           |   |   |
| Additions                                                                                                                                        | $ 145          |           | $ 145 |   |
| Accretion                                                                                                                                        | $ (12)         |           | $ (12) |   |
| Reclassification from nonaccretable                                                                                                              |           |           |   |   |
| Disposals                                                                                                                                        |           |           |   |   |
| Ending balance                                                                                                                                   | $ 133          |           | $ 133 |   |
| Merger with Community Bancshares, Inc.                                                                                                           |           |           |   |   |
| **Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Accretable Yield Movement Schedule [Roll Forward]**                   |           |           |   |   |
| Beginning balance                                                                                                                                | $ 1,990        |           | $ 2,122 |   |
| Additions                                                                                                                                        |           |           |   |   |
| Accretion                                                                                                                                        | $ (353)        |           | $ (532) |   |
| Reclassification from nonaccretable                                                                                                              | $ 181          |           | $ 228 |   |
| Disposals                                                                                                                                        |           |           |   |   |
| Ending balance                                                                                                                                   | $ 1,818        |           | $ 1,818 |   |
| Merger with CFS Bancorp, Inc. (Citizens)                                                                                                         |           |           |   |   |
| **Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Accretable Yield Movement Schedule [Roll Forward]**                   |           |           |   |   |
| Beginning balance                                                                                                                                | $ 2,009        | $ 4,080        | $ 2,400 | $ 4,164 |
| Additions                                                                                                                                        |           |           |   |   |
| Accretion                                                                                                                                        | $ (578)        | $ (1,242)      | $ (1,919) | $ (1,543) |
| Reclassification from nonaccretable                                                                                                              | 309            | $ 650          | 1,259 | 902 |
| Disposals                                                                                                                                        | (8)            |           | (8) | (35) |
| Ending balance                                                                                                                                   | 1,732          | $ 3,488        | 1,732 | 3,488 |
| SCB Bank                                                                                                                                         |           |           |   |   |
| **Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Accretable Yield Movement Schedule [Roll Forward]**                   |           |           |   |   |
| Beginning balance                                                                                                                                | 818            | 1,256          | 868 | 1,388 |
| Accretion                                                                                                                                        | (304)          | (215)          | (489) | (402) |
| Reclassification from nonaccretable                                                                                                              | $ 244          | $ 129          | $ 379 | $ 184 |
| Disposals                                                                                                                                        |           |           |   |   |
| Ending balance                                                                                                                                   | $ 758          | $ 1,170        | $ 758 | $ 1,170 |

| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                      |
|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
The aggregate excess of a loan's cash flows expected to be collected over the investor's initial investment in the loan for loans accounted for as debt securities, with evidence of deterioration of credit quality since origination that were acquired by completion of a transfer for which it is probable, at acquisition, that the investor will be unable to collect all contractually required payments receivable.
+ References
Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 30 -Section 15 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=27045933&loc=d3e13503-111538Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 30 -Section 50 -Paragraph 2 -Subparagraph (a)(2) -URI http://asc.fasb.org/extlink&oid=6379141&loc=d3e15032-111544
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|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Current period recognition due to accretion of the excess of a loan's cash flows expected to be collected over the investor's initial investment in the loan for loans accounted for as debt securities, with evidence of deterioration of credit quality since origination that were acquired by completion of a transfer for which it is probable, at acquisition, that the investor will be unable to collect all contractually required payments receivable.
+ References
Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 30 -Section 15 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=27045933&loc=d3e13503-111538Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 30 -Section 50 -Paragraph 2 -Subparagraph (a)(2) -URI http://asc.fasb.org/extlink&oid=6379141&loc=d3e15032-111544
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|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Increases in the aggregate excess of a loan's cash flows expected to be collected over the investor's initial investment in the loan due to the acquisition of similar loans accounted for as debt securities during the period. This relates to loans accounted for as debt securities, with evidence of deterioration of credit quality since origination that were acquired by completion of a transfer for which it is probable, at acquisition, that the investor will be unable to collect all contractually required payments receivable.
+ References
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|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Sale or transfer of a loan during the period resulting in a reduction in the excess of a loan's cash flows expected to be collected over the investor's initial investment.  This relates to loans accounted for as debt securities, with evidence of deterioration of credit quality since origination that was acquired by completion of a transfer for which it is probable, at acquisition, that the investor will be unable to collect all contractually required payments receivable.
+ References
Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 30 -Section 15 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=27045933&loc=d3e13503-111538Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 30 -Section 50 -Paragraph 2 -Subparagraph (a)(2) -URI http://asc.fasb.org/extlink&oid=6379141&loc=d3e15032-111544
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|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Change in the estimate of cash flows expected to be collected, after acquisition of a loan, which results in an increase in accretable yield (for example, if actual cash flows are significantly greater than previously expected).  This relates to loans accounted for as debt securities, with evidence of deterioration of credit quality since origination that was acquired by completion of a transfer for which it is probable, at acquisition, that the investor will be unable to collect all contractually required payments receivable.
+ References
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| X                                                                                                                                                                                                                                                                                                                                                                                                     |
|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.
+ References
No definition available.
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| X                                                                                                                                                                    |
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| X                                                                                                                                                                   |
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| X                                                                                                                                          |
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