Loans (Schedule of Aging of Recorded Investment in Loans) (Details) - USD ($) $ in Thousands	Mar. 31, 2016		Dec. 31, 2015
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Loans	$ 1,927,304	[1],[2]	$ 1,574,027	[3],[4]
Loans Past Due	14,022	[2]	4,831	[3]
Loans Not Past Due	1,913,282	[2]	1,569,196	[3]
Accrued interest	8,666		5,952
Commercial and Industrial Loans and Leases
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Loans	449,827	[1]	419,176	[4]
Loans Past Due	660		323
Loans Not Past Due	449,167		418,853
Commercial Real Estate Loans
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Loans	814,556	[1]	620,163	[4]
Loans Past Due	3,879		403
Loans Not Past Due	810,677		619,760
Agricultural Loans
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Loans	280,166	[1]	249,699	[4]
Loans Past Due	2,454		0
Loans Not Past Due	277,712		249,699
Home Equity Loans
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Loans	119,369	[1]	98,167	[4]
Loans Past Due	548		437
Loans Not Past Due	118,821		97,730
Consumer Loans
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Loans	55,174	[1]	50,169	[4]
Loans Past Due	524		231
Loans Not Past Due	54,650		49,938
Residential Mortgage Loans
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Loans	208,212	[1]	136,653	[4]
Loans Past Due	5,957		3,437
Loans Not Past Due	202,255		133,216
30-59 Days Past Due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans Past Due	8,284	[2]	3,159	[3]
30-59 Days Past Due | Commercial and Industrial Loans and Leases
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans Past Due	555		82
30-59 Days Past Due | Commercial Real Estate Loans
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans Past Due	1,758		136
30-59 Days Past Due | Agricultural Loans
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans Past Due	1,227		0
30-59 Days Past Due | Home Equity Loans
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans Past Due	335		225
30-59 Days Past Due | Consumer Loans
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans Past Due	150		101
30-59 Days Past Due | Residential Mortgage Loans
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans Past Due	4,259		2,615
60-89 Days Past Due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans Past Due	2,042	[2]	482	[3]
60-89 Days Past Due | Commercial and Industrial Loans and Leases
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans Past Due	80		117
60-89 Days Past Due | Commercial Real Estate Loans
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans Past Due	664		163
60-89 Days Past Due | Agricultural Loans
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans Past Due	387		0
60-89 Days Past Due | Home Equity Loans
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans Past Due	79		8
60-89 Days Past Due | Consumer Loans
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans Past Due	196		40
60-89 Days Past Due | Residential Mortgage Loans
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans Past Due	636		154
90 Days or More Past Due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans Past Due	3,696	[2]	1,190	[3]
90 Days or More Past Due | Commercial and Industrial Loans and Leases
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans Past Due	25		124
90 Days or More Past Due | Commercial Real Estate Loans
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans Past Due	1,457		104
90 Days or More Past Due | Agricultural Loans
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans Past Due	840		0
90 Days or More Past Due | Home Equity Loans
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans Past Due	134		204
90 Days or More Past Due | Consumer Loans
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans Past Due	178		90
90 Days or More Past Due | Residential Mortgage Loans
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans Past Due	1,062		668
Receivables Acquired with Deteriorated Credit Quality | Loans Acquired With Deteriorated Credit Quality (Included in the Total Above)
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Loans	15,351		7,555
Loans Past Due	2,419		0
Loans Not Past Due	12,932		7,555
Receivables Acquired with Deteriorated Credit Quality | 30-59 Days Past Due | Loans Acquired With Deteriorated Credit Quality (Included in the Total Above)
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans Past Due	392		0
Receivables Acquired with Deteriorated Credit Quality | 60-89 Days Past Due | Loans Acquired With Deteriorated Credit Quality (Included in the Total Above)
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans Past Due	568		0
Receivables Acquired with Deteriorated Credit Quality | 90 Days or More Past Due | Loans Acquired With Deteriorated Credit Quality (Included in the Total Above)
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans Past Due	1,459		$ 0
River Valley Bancorp
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Loans	318,882
Loans Past Due	8,836
Loans Not Past Due	310,046
River Valley Bancorp | 30-59 Days Past Due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans Past Due	4,789
River Valley Bancorp | 60-89 Days Past Due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans Past Due	1,195
River Valley Bancorp | 90 Days or More Past Due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans Past Due	$ 2,852

[1] Total recorded investment in loans includes $8,666 in accrued interest.

[2] Total recorded investment in loans includes $8,666 in accrued interest.

[3] Total recorded investment in loans includes $5,952 in accrued interest.

[4] Total recorded investment in loans includes $5,952 in accrued interest.