| **Accounting for Certain Loans Acquired in a Purchase (Tables)**                                               | 9 Months Ended                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                      |
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| **Receivables [Abstract]**                                                                                     |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                |
| Schedule of Carrying Values of Certain Loans Acquired in a Transfer Not Accounted for as Debt Securities       | The following table includes the carrying amount of these loans, which are included in the balance sheet amounts of loans receivable at September 30, 2013 and December 31, 2012. September 30, 2013December 31, 2012Commercial and industrial loans$6,265$8,542Agricultural production financing and other loans to farmers1,3821,127Real estate loans:  Construction858Commercial and farmland18,55324,259Residential9,61412,118       Home Equity16,52918,805Individuals' loans for household and other personal expenditures336691Other Loans164Total$52,851$65,600 |
| Schedule of Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Accretable Yield Movement | Accretable yield, or income expected to be collected, is as follows: Three Months EndedSeptember 30, 2013Nine Months Ended September 30, 2013Beginning balance$3,959$5,142Accretion(413)(1,596)Ending balance, September 30, 2013$3,546$3,546 Three Months Ended September 30, 2012Nine Months Ended September 30, 2012Beginning balance$9,048$9,774Accretion(2,612)(3,338)Ending balance, September 30, 2012$6,436$6,436                                                                                                                                                                                                 |

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Schedule of Carrying Values of Certain Loans Acquired in Transfer Not Accounted for as Debt Securities [Table Text Block]
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Schedule of Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Accretable Yield Movement [Table Text Block]
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