| **Accounting for Certain Loans Acquired in a Purchase (Tables)**                                                 | 3 Months Ended                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                |
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| **Receivables [Abstract]**                                                                                       |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                          |
| Schedule of outstanding balance and carrying amount of loans acquired during the period                          | The following table includes the outstanding balance and carrying amount of all acquired loans which were included in the Corporation's balance sheet at March 31, 2016, and December 31, 2015.March 31, 2016Ameriana C FinancialCommunityCFSSCBTotalCommercial and industrial loans$23,363 $99$7,224$50,476$4,351$85,513Agricultural production financing and other loans to farmers 2,4721,2633,735Real estate loans:  Construction30,414 6,9289,68186247,885Commercial and farmland131,371 25,72947,190175,69212,494392,476Residential116,116 52,72019,212113,6335,645307,326       Home Equity13,390 8,8247,44530,70513,00073,364Individuals' loans for household and other personal expenditures1,433 8306348432,138Other commercial loans1,840 701,910Total$317,927 $94,308$93,530$371,786$36,796$914,347 Carrying Amount$304,615 $92,097$87,523$353,882$32,390$870,507Allowance 10550155Carrying Amount Net of Allowance$304,615 $92,097$87,418$353,832$32,390$870,352December 31, 2015Ameriana C Financial CommunityCFSSCBTotalCommercial and industrial loans$21,888 $104 $6,769$52,060$4,620$85,441Agricultural production financing and other loans to farmers   1,7611,2883,049Real estate loans:    Construction23,365 6,214 10,43697640,991Commercial and farmland144,514 27,838 49,997189,37213,293425,014Residential123,231 55,856 21,886118,1056,063325,141       Home Equity14,261 9,144 8,23131,98613,43177,053Individuals' loans for household and other personal expenditures1,731 10 461443482,693Other commercial loans1,928   722,000Total$330,918 $99,166 $99,541$393,014$38,743$961,382   Carrying Amount$319,664 $96,829 $93,355$373,649$34,092$917,589Allowance   4149153Carrying Amount Net of Allowance$319,664 $96,829 $93,351$373,500$34,092$917,436 |
| Schedule of accretable yield, or income expected to be collected, and reclassifications from nonaccretable yield | The accretable yield, or income expected to be collected, and reclassifications from nonaccretable yield, are identified in the table below.  The table reflects only purchased loans accounted for under ASC 310-30 and not the entire portfolio of purchased loans.Three Months Ended March 31, 2016Ameriana C FinancialCommunityCFSSCBTotalBeginning balance$2,160 $114$1,508$1,188$642$5,612Additions Accretion(40) (15)(63)(1,290)(88)(1,496)Reclassification from nonaccretable 1111,135361,183Disposals Ending balance$2,120 $100$1,456$1,033$590$5,299          Three Months Ended March 31, 2015Community CFSSCBTotalBeginning balance$2,122 $2,400$868$5,390Additions Accretion(179) (1,341)(185)(1,705)Reclassification from nonaccretable47 9501351,132Disposals Ending balance$1,990 $2,009$818$4,817                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               |

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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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