Loans (Schedule of Risk Category of Loans) (Details) - USD ($) $ in Thousands	Dec. 31, 2016		Dec. 31, 2015		Dec. 31, 2014
Financing Receivable, Recorded Investment [Line Items]
Total Ending Loans Balance	$ 2,001,415	[1],[2]	$ 1,574,027	[3],[4]
Commercial and Industrial Loans and Leases
Financing Receivable, Recorded Investment [Line Items]
Total Ending Loans Balance	458,538	[2]	419,176	[4]
Commercial Real Estate Loans
Financing Receivable, Recorded Investment [Line Items]
Total Ending Loans Balance	858,030	[2]	620,163	[4]
Agricultural Loans
Financing Receivable, Recorded Investment [Line Items]
Total Ending Loans Balance	306,946	[2]	249,699	[4]
River Valley Bancorp
Financing Receivable, Recorded Investment [Line Items]
Total Ending Loans Balance	262,809
Loans Acquired with Deteriorated Credit Quality
Financing Receivable, Recorded Investment [Line Items]
Total Ending Loans Balance	11,048	[2]	7,555	[2]	$ 8,361
Loans Acquired with Deteriorated Credit Quality | Commercial and Industrial Loans and Leases
Financing Receivable, Recorded Investment [Line Items]
Total Ending Loans Balance	1,656	[2]	1,325	[2]	354
Loans Acquired with Deteriorated Credit Quality | Commercial Real Estate Loans
Financing Receivable, Recorded Investment [Line Items]
Total Ending Loans Balance	7,688	[2]	5,363	[2]	6,385
Loans Acquired with Deteriorated Credit Quality | Agricultural Loans
Financing Receivable, Recorded Investment [Line Items]
Total Ending Loans Balance	706	[2]	0	[2]	$ 0
Pass
Financing Receivable, Recorded Investment [Line Items]
Total Ending Loans Balance	1,539,361		1,222,245
Pass | Commercial and Industrial Loans and Leases
Financing Receivable, Recorded Investment [Line Items]
Total Ending Loans Balance	437,353		393,270
Pass | Commercial Real Estate Loans
Financing Receivable, Recorded Investment [Line Items]
Total Ending Loans Balance	814,033		586,247
Pass | Agricultural Loans
Financing Receivable, Recorded Investment [Line Items]
Total Ending Loans Balance	287,975		242,728
Pass | River Valley Bancorp
Financing Receivable, Recorded Investment [Line Items]
Total Ending Loans Balance	175,915
Pass | Loans Acquired with Deteriorated Credit Quality
Financing Receivable, Recorded Investment [Line Items]
Total Ending Loans Balance	1,897		1,572
Special Mention
Financing Receivable, Recorded Investment [Line Items]
Total Ending Loans Balance	51,673		44,193
Special Mention | Commercial and Industrial Loans and Leases
Financing Receivable, Recorded Investment [Line Items]
Total Ending Loans Balance	10,454		13,675
Special Mention | Commercial Real Estate Loans
Financing Receivable, Recorded Investment [Line Items]
Total Ending Loans Balance	26,549		25,341
Special Mention | Agricultural Loans
Financing Receivable, Recorded Investment [Line Items]
Total Ending Loans Balance	14,670		5,177
Special Mention | River Valley Bancorp
Financing Receivable, Recorded Investment [Line Items]
Total Ending Loans Balance	11,638
Special Mention | Loans Acquired with Deteriorated Credit Quality
Financing Receivable, Recorded Investment [Line Items]
Total Ending Loans Balance	3,121		3,319
Substandard
Financing Receivable, Recorded Investment [Line Items]
Total Ending Loans Balance	32,480		22,600
Substandard | Commercial and Industrial Loans and Leases
Financing Receivable, Recorded Investment [Line Items]
Total Ending Loans Balance	10,731		12,231
Substandard | Commercial Real Estate Loans
Financing Receivable, Recorded Investment [Line Items]
Total Ending Loans Balance	17,448		8,575
Substandard | Agricultural Loans
Financing Receivable, Recorded Investment [Line Items]
Total Ending Loans Balance	4,301		1,794
Substandard | River Valley Bancorp
Financing Receivable, Recorded Investment [Line Items]
Total Ending Loans Balance	8,145
Substandard | Loans Acquired with Deteriorated Credit Quality
Financing Receivable, Recorded Investment [Line Items]
Total Ending Loans Balance	5,032		1,797
Doubtful
Financing Receivable, Recorded Investment [Line Items]
Total Ending Loans Balance	0		0
Doubtful | Commercial and Industrial Loans and Leases
Financing Receivable, Recorded Investment [Line Items]
Total Ending Loans Balance	0		0
Doubtful | Commercial Real Estate Loans
Financing Receivable, Recorded Investment [Line Items]
Total Ending Loans Balance	0		0
Doubtful | Agricultural Loans
Financing Receivable, Recorded Investment [Line Items]
Total Ending Loans Balance	0		0
Doubtful | River Valley Bancorp
Financing Receivable, Recorded Investment [Line Items]
Total Ending Loans Balance	0
Doubtful | Loans Acquired with Deteriorated Credit Quality
Financing Receivable, Recorded Investment [Line Items]
Total Ending Loans Balance	0		0
Total by Risk Category
Financing Receivable, Recorded Investment [Line Items]
Total Ending Loans Balance	1,623,514		1,289,038
Total by Risk Category | Commercial and Industrial Loans and Leases
Financing Receivable, Recorded Investment [Line Items]
Total Ending Loans Balance	458,538		419,176
Total by Risk Category | Commercial Real Estate Loans
Financing Receivable, Recorded Investment [Line Items]
Total Ending Loans Balance	858,030		620,163
Total by Risk Category | Agricultural Loans
Financing Receivable, Recorded Investment [Line Items]
Total Ending Loans Balance	306,946		249,699
Total by Risk Category | River Valley Bancorp
Financing Receivable, Recorded Investment [Line Items]
Total Ending Loans Balance	195,698
Total by Risk Category | Loans Acquired with Deteriorated Credit Quality
Financing Receivable, Recorded Investment [Line Items]
Total Ending Loans Balance	$ 10,050		$ 6,688

[1] Total recorded investment in loans includes $8,011 in accrued interest.

[2] Total recorded investment in loans includes $8,011 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.