Loans (Schedule of Risk Category of Loans) (Details) - USD ($) $ in Thousands	Mar. 31, 2016		Dec. 31, 2015
Financing Receivable, Recorded Investment [Line Items]
Total loans and leases	$ 1,927,304	[1],[2]	$ 1,574,027	[3],[4]
Commercial and Industrial Loans and Leases
Financing Receivable, Recorded Investment [Line Items]
Total loans and leases	449,827	[1]	419,176	[4]
Commercial Real Estate Loans
Financing Receivable, Recorded Investment [Line Items]
Total loans and leases	814,556	[1]	620,163	[4]
Agricultural Loans
Financing Receivable, Recorded Investment [Line Items]
Total loans and leases	280,166	[1]	249,699	[4]
Pass
Financing Receivable, Recorded Investment [Line Items]
Total loans and leases	1,449,266		1,222,245
Pass | Commercial and Industrial Loans and Leases
Financing Receivable, Recorded Investment [Line Items]
Total loans and leases	425,412		393,270
Pass | Commercial Real Estate Loans
Financing Receivable, Recorded Investment [Line Items]
Total loans and leases	763,617		586,247
Pass | Agricultural Loans
Financing Receivable, Recorded Investment [Line Items]
Total loans and leases	260,237		242,728
Special Mention
Financing Receivable, Recorded Investment [Line Items]
Total loans and leases	67,037		44,193
Special Mention | Commercial and Industrial Loans and Leases
Financing Receivable, Recorded Investment [Line Items]
Total loans and leases	13,772		13,675
Special Mention | Commercial Real Estate Loans
Financing Receivable, Recorded Investment [Line Items]
Total loans and leases	36,345		25,341
Special Mention | Agricultural Loans
Financing Receivable, Recorded Investment [Line Items]
Total loans and leases	16,920		5,177
Substandard
Financing Receivable, Recorded Investment [Line Items]
Total loans and leases	28,246		22,600
Substandard | Commercial and Industrial Loans and Leases
Financing Receivable, Recorded Investment [Line Items]
Total loans and leases	10,643		12,231
Substandard | Commercial Real Estate Loans
Financing Receivable, Recorded Investment [Line Items]
Total loans and leases	14,594		8,575
Substandard | Agricultural Loans
Financing Receivable, Recorded Investment [Line Items]
Total loans and leases	3,009		1,794
Doubtful
Financing Receivable, Recorded Investment [Line Items]
Total loans and leases	0		0
Doubtful | Commercial and Industrial Loans and Leases
Financing Receivable, Recorded Investment [Line Items]
Total loans and leases	0		0
Doubtful | Commercial Real Estate Loans
Financing Receivable, Recorded Investment [Line Items]
Total loans and leases	0		0
Doubtful | Agricultural Loans
Financing Receivable, Recorded Investment [Line Items]
Total loans and leases	0		0
Total
Financing Receivable, Recorded Investment [Line Items]
Total loans and leases	1,544,549		1,289,038
Total | Commercial and Industrial Loans and Leases
Financing Receivable, Recorded Investment [Line Items]
Total loans and leases	449,827		419,176
Total | Commercial Real Estate Loans
Financing Receivable, Recorded Investment [Line Items]
Total loans and leases	814,556		620,163
Total | Agricultural Loans
Financing Receivable, Recorded Investment [Line Items]
Total loans and leases	280,166		249,699
Receivables Acquired with Deteriorated Credit Quality
Financing Receivable, Recorded Investment [Line Items]
Loans Acquired With Deteriorated Credit Quality (Included in the Total Above)	15,351		7,555
Receivables Acquired with Deteriorated Credit Quality | Commercial and Industrial Loans and Leases
Financing Receivable, Recorded Investment [Line Items]
Loans Acquired With Deteriorated Credit Quality (Included in the Total Above)	1,115		1,325
Receivables Acquired with Deteriorated Credit Quality | Commercial Real Estate Loans
Financing Receivable, Recorded Investment [Line Items]
Loans Acquired With Deteriorated Credit Quality (Included in the Total Above)	10,552		5,363
Receivables Acquired with Deteriorated Credit Quality | Agricultural Loans
Financing Receivable, Recorded Investment [Line Items]
Loans Acquired With Deteriorated Credit Quality (Included in the Total Above)	1,086		0
Receivables Acquired with Deteriorated Credit Quality | Pass
Financing Receivable, Recorded Investment [Line Items]
Loans Acquired With Deteriorated Credit Quality (Included in the Total Above)	1,265		1,572
Receivables Acquired with Deteriorated Credit Quality | Special Mention
Financing Receivable, Recorded Investment [Line Items]
Loans Acquired With Deteriorated Credit Quality (Included in the Total Above)	3,347		3,319
Receivables Acquired with Deteriorated Credit Quality | Substandard
Financing Receivable, Recorded Investment [Line Items]
Loans Acquired With Deteriorated Credit Quality (Included in the Total Above)	8,141		1,797
Receivables Acquired with Deteriorated Credit Quality | Doubtful
Financing Receivable, Recorded Investment [Line Items]
Loans Acquired With Deteriorated Credit Quality (Included in the Total Above)	0		0
Receivables Acquired with Deteriorated Credit Quality | Total
Financing Receivable, Recorded Investment [Line Items]
Loans Acquired With Deteriorated Credit Quality (Included in the Total Above)	12,753		$ 6,688
River Valley Bancorp
Financing Receivable, Recorded Investment [Line Items]
Total loans and leases	318,882
River Valley Bancorp | Pass
Financing Receivable, Recorded Investment [Line Items]
Loans Acquired With Deteriorated Credit Quality (Included in the Total Above)	201,554
River Valley Bancorp | Special Mention
Financing Receivable, Recorded Investment [Line Items]
Loans Acquired With Deteriorated Credit Quality (Included in the Total Above)	17,759
River Valley Bancorp | Substandard
Financing Receivable, Recorded Investment [Line Items]
Loans Acquired With Deteriorated Credit Quality (Included in the Total Above)	7,289
River Valley Bancorp | Doubtful
Financing Receivable, Recorded Investment [Line Items]
Loans Acquired With Deteriorated Credit Quality (Included in the Total Above)	0
River Valley Bancorp | Total
Financing Receivable, Recorded Investment [Line Items]
Loans Acquired With Deteriorated Credit Quality (Included in the Total Above)	$ 226,602

[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.