| **Accounting For Certain Loans Acquired In a Purchase - Carrying Amount of Loans Included in Balance Sheet (Details) (USD $)In Thousands, unless otherwise specified** | Dec. 31, 2013 | Dec. 31, 2012 |
|------------------------------------------------------------------------------------------------------------------------------------------------------------------------|---------------|---------------|
| **Accounts, Notes, Loans and Financing Receivable [Line Items]**                                                                                                       |          |          |
| Loans Acquired                                                                                                                                                         | $ 690,218     |          |
| Carrying Amount                                                                                                                                                        | 636,182       |          |
| Allowance                                                                                                                                                              | 229           | 0             |
| Carrying Amount                                                                                                                                                        | 635,953       |          |
| Merger with CFS Bancorp, Inc. (Citizens)                                                                                                                               |          |          |
| **Accounts, Notes, Loans and Financing Receivable [Line Items]**                                                                                                       |          |          |
| Loans Acquired                                                                                                                                                         | 629,184       |          |
| Carrying Amount                                                                                                                                                        | 585,913       |          |
| Carrying Amount                                                                                                                                                        | 585,913       |          |
| SCB Bank                                                                                                                                                               |          |          |
| **Accounts, Notes, Loans and Financing Receivable [Line Items]**                                                                                                       |          |          |
| Loans Acquired                                                                                                                                                         | 61,034        | 80,165        |
| Carrying Amount                                                                                                                                                        | 50,269        | 65,600        |
| Allowance                                                                                                                                                              | 229           |          |
| Carrying Amount                                                                                                                                                        | 50,040        | 65,600        |
| Commercial and industrial loans                                                                                                                                        |          |          |
| **Accounts, Notes, Loans and Financing Receivable [Line Items]**                                                                                                       |          |          |
| Loans Acquired                                                                                                                                                         | 89,487        |          |
| Commercial and industrial loans | Merger with CFS Bancorp, Inc. (Citizens)                                                                                             |          |          |
| **Accounts, Notes, Loans and Financing Receivable [Line Items]**                                                                                                       |          |          |
| Loans Acquired                                                                                                                                                         | 81,303        |          |
| Commercial and industrial loans | SCB Bank                                                                                                                             |          |          |
| **Accounts, Notes, Loans and Financing Receivable [Line Items]**                                                                                                       |          |          |
| Loans Acquired                                                                                                                                                         | 8,184         | 12,645        |
| Agriculture Production financing and other loans to farmers                                                                                                            |          |          |
| **Accounts, Notes, Loans and Financing Receivable [Line Items]**                                                                                                       |          |          |
| Loans Acquired                                                                                                                                                         | 1,161         |          |
| Agriculture Production financing and other loans to farmers | SCB Bank                                                                                                 |          |          |
| **Accounts, Notes, Loans and Financing Receivable [Line Items]**                                                                                                       |          |          |
| Loans Acquired                                                                                                                                                         | 1,161         | 1,179         |
| Construction                                                                                                                                                           |          |          |
| **Accounts, Notes, Loans and Financing Receivable [Line Items]**                                                                                                       |          |          |
| Loans Acquired                                                                                                                                                         | 17,962        |          |
| Construction | Merger with CFS Bancorp, Inc. (Citizens)                                                                                                                |          |          |
| **Accounts, Notes, Loans and Financing Receivable [Line Items]**                                                                                                       |          |          |
| Loans Acquired                                                                                                                                                         | 17,962        |          |
| Construction | SCB Bank                                                                                                                                                |          |          |
| **Accounts, Notes, Loans and Financing Receivable [Line Items]**                                                                                                       |          |          |
| Loans Acquired                                                                                                                                                         |          | 65            |
| Commercial and farmland                                                                                                                                                |          |          |
| **Accounts, Notes, Loans and Financing Receivable [Line Items]**                                                                                                       |          |          |
| Loans Acquired                                                                                                                                                         | 335,049       |          |
| Commercial and farmland | Merger with CFS Bancorp, Inc. (Citizens)                                                                                                     |          |          |
| **Accounts, Notes, Loans and Financing Receivable [Line Items]**                                                                                                       |          |          |
| Loans Acquired                                                                                                                                                         | 311,631       |          |
| Commercial and farmland | SCB Bank                                                                                                                                     |          |          |
| **Accounts, Notes, Loans and Financing Receivable [Line Items]**                                                                                                       |          |          |
| Loans Acquired                                                                                                                                                         | 23,418        | 30,303        |
| Residential                                                                                                                                                            |          |          |
| **Accounts, Notes, Loans and Financing Receivable [Line Items]**                                                                                                       |          |          |
| Loans Acquired                                                                                                                                                         | 176,113       |          |
| Residential | Merger with CFS Bancorp, Inc. (Citizens)                                                                                                                 |          |          |
| **Accounts, Notes, Loans and Financing Receivable [Line Items]**                                                                                                       |          |          |
| Loans Acquired                                                                                                                                                         | 166,754       |          |
| Residential | SCB Bank                                                                                                                                                 |          |          |
| **Accounts, Notes, Loans and Financing Receivable [Line Items]**                                                                                                       |          |          |
| Loans Acquired                                                                                                                                                         | 9,359         | 13,724        |
| Home Equity                                                                                                                                                            |          |          |
| **Accounts, Notes, Loans and Financing Receivable [Line Items]**                                                                                                       |          |          |
| Loans Acquired                                                                                                                                                         | 67,278        |          |
| Home Equity | Merger with CFS Bancorp, Inc. (Citizens)                                                                                                                 |          |          |
| **Accounts, Notes, Loans and Financing Receivable [Line Items]**                                                                                                       |          |          |
| Loans Acquired                                                                                                                                                         | 49,042        |          |
| Home Equity | SCB Bank                                                                                                                                                 |          |          |
| **Accounts, Notes, Loans and Financing Receivable [Line Items]**                                                                                                       |          |          |
| Loans Acquired                                                                                                                                                         | 18,236        | 21,544        |
| Individuals' loans for household and other personal expenditures                                                                                                       |          |          |
| **Accounts, Notes, Loans and Financing Receivable [Line Items]**                                                                                                       |          |          |
| Loans Acquired                                                                                                                                                         | 2,629         |          |
| Individuals' loans for household and other personal expenditures | Merger with CFS Bancorp, Inc. (Citizens)                                                            |          |          |
| **Accounts, Notes, Loans and Financing Receivable [Line Items]**                                                                                                       |          |          |
| Loans Acquired                                                                                                                                                         | 2,360         |          |
| Individuals' loans for household and other personal expenditures | SCB Bank                                                                                            |          |          |
| **Accounts, Notes, Loans and Financing Receivable [Line Items]**                                                                                                       |          |          |
| Loans Acquired                                                                                                                                                         | 269           | 705           |
| Other loans                                                                                                                                                            |          |          |
| **Accounts, Notes, Loans and Financing Receivable [Line Items]**                                                                                                       |          |          |
| Loans Acquired                                                                                                                                                         | 539           |     |
| Other loans | Merger with CFS Bancorp, Inc. (Citizens)                                                                                                                 |          |          |
| **Accounts, Notes, Loans and Financing Receivable [Line Items]**                                                                                                       |          |          |
| Loans Acquired                                                                                                                                                         | 132           |          |
| Other loans | SCB Bank                                                                                                                                                 |          |          |
| **Accounts, Notes, Loans and Financing Receivable [Line Items]**                                                                                                       |          |          |
| Loans Acquired                                                                                                                                                         | $ 407         |          |

| X                                                                                                                                                                                                                                                                                                                                                                    |
|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Carrying Amount Gross
+ References
No definition available.
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| X                                                                                                                                                                            |
|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
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|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
The undiscounted sum of all amounts, including amounts deemed principal, interest, fees, penalties, and other under the loan, owed to the investor at the reporting date, whether or not currently due and whether or not any such amounts have been written or charged off by the investor.  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
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)(1) -URI http://asc.fasb.org/extlink&oid=6379141&loc=d3e15032-111544
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|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Reserve for loans impairments recorded after acquisition as a result of current information and events which result in it being probable that estimated cash flows will be less than previously expected or because actual cash flows are less than cash flows previously expected.  This relates to loans not 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 (b)(2) -URI http://asc.fasb.org/extlink&oid=6379141&loc=d3e15032-111544
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|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
The recorded balance, net of any applicable reductions (for example, unamortized accretable yield and allowance for loan losses).  This relates to loans not accounted for 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)(1) -URI http://asc.fasb.org/extlink&oid=6379141&loc=d3e15032-111544
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