Accounting for Certain Loans Acquired in a Purchase - Carrying Amount of Loans Included in Balance Sheet (Details) - USD ($) $ in Thousands	Sep. 30, 2016	Dec. 31, 2015
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	$ 769,357	$ 961,382
Carrying Amount	733,715	917,589
Allowance	664	153
Carrying Amount Net of Allowance	733,051	917,436
Loans acquired and accounted for under ASC 310-30, outstanding balance	71,100	95,800
Loans acquired and accounted for under ASC 310-30, carrying amount	51,800	69,600
Commercial and industrial loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	54,403	85,441
Agricultural production financing and other loans to farmers
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	3,578	3,049
Real estate loans - Construction
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	40,502	40,991
Real estate loans - Commercial and farmland
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	331,232	425,014
Real estate loans - Residential
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	268,101	325,141
Real estate loans - Home Equity
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	68,233	77,053
Individuals' loans for household and other personal expenditures
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	1,416	2,693
Other commercial loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	1,892	2,000
Ameriana
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	277,963	330,918
Carrying Amount	266,592	319,664
Carrying Amount Net of Allowance	266,592	319,664
Ameriana | Commercial and industrial loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	16,731	21,888
Ameriana | Real estate loans - Construction
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	30,800	23,365
Ameriana | Real estate loans - Commercial and farmland
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	110,195	144,514
Ameriana | Real estate loans - Residential
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	105,173	123,231
Ameriana | Real estate loans - Home Equity
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	12,301	14,261
Ameriana | Individuals' loans for household and other personal expenditures
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	938	1,731
Ameriana | Other commercial loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	1,825	1,928
C Financial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	81,009	99,166
Carrying Amount	78,972	96,829
Allowance
Carrying Amount Net of Allowance	78,972	96,829
C Financial | Commercial and industrial loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	90	104
C Financial | Real estate loans - Construction
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	3,260	6,214
C Financial | Real estate loans - Commercial and farmland
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	22,449	27,838
C Financial | Real estate loans - Residential
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	46,696	55,856
C Financial | Real estate loans - Home Equity
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	8,511	9,144
C Financial | Individuals' loans for household and other personal expenditures
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	3	10
Community
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	68,512	99,541
Carrying Amount	64,149	93,355
Allowance	22	4
Carrying Amount Net of Allowance	64,127	93,351
Community | Commercial and industrial loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	3,239	6,769
Community | Agricultural production financing and other loans to farmers
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	2,223	1,761
Community | Real estate loans - Construction
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	5,953	10,436
Community | Real estate loans - Commercial and farmland
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	39,765	49,997
Community | Real estate loans - Residential
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	10,091	21,886
Community | Real estate loans - Home Equity
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	7,038	8,231
Community | Individuals' loans for household and other personal expenditures
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	203	461
CFS
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	309,051	393,014
Carrying Amount	294,759	373,649
Allowance	642	149
Carrying Amount Net of Allowance	294,117	373,500
CFS | Commercial and industrial loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	30,553	52,060
CFS | Agricultural production financing and other loans to farmers
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	50
CFS | Real estate loans - Construction
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	489	976
CFS | Real estate loans - Commercial and farmland
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	147,890	189,372
CFS | Real estate loans - Residential
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	101,663	118,105
CFS | Real estate loans - Home Equity
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	28,101	31,986
CFS | Individuals' loans for household and other personal expenditures
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	238	443
CFS | Other commercial loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	67	72
SCB
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	32,822	38,743
Carrying Amount	29,243	34,092
Carrying Amount Net of Allowance	29,243	34,092
SCB | Commercial and industrial loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	3,790	4,620
SCB | Agricultural production financing and other loans to farmers
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	1,305	1,288
SCB | Real estate loans - Commercial and farmland
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	10,933	13,293
SCB | Real estate loans - Residential
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	4,478	6,063
SCB | Real estate loans - Home Equity
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	12,282	13,431
SCB | Individuals' loans for household and other personal expenditures
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	$ 34	$ 48