Loans (Schedule of Risk Category of Loans) (Details) - USD ($) $ in Thousands		Jun. 30, 2017	Dec. 31, 2016
Financing Receivable, Recorded Investment [Line Items]
Loans, net of deferred income	[1]	$ 2,042,770	$ 2,001,415
Receivables Acquired with Deteriorated Credit Quality
Financing Receivable, Recorded Investment [Line Items]
Loans, net of deferred income	[1]	9,513	11,048
Receivables Acquired with Deteriorated Credit Quality | River Valley Bancorp
Financing Receivable, Recorded Investment [Line Items]
Loans, net of deferred income			262,809
Pass
Financing Receivable, Recorded Investment [Line Items]
Loans, net of deferred income		1,570,754	1,539,361
Pass | Receivables Acquired with Deteriorated Credit Quality
Financing Receivable, Recorded Investment [Line Items]
Loans, net of deferred income		1,479	1,897
Pass | Receivables Acquired with Deteriorated Credit Quality | River Valley Bancorp
Financing Receivable, Recorded Investment [Line Items]
Loans, net of deferred income			175,915
Special Mention
Financing Receivable, Recorded Investment [Line Items]
Loans, net of deferred income		58,887	51,673
Special Mention | Receivables Acquired with Deteriorated Credit Quality
Financing Receivable, Recorded Investment [Line Items]
Loans, net of deferred income		3,120	3,121
Special Mention | Receivables Acquired with Deteriorated Credit Quality | River Valley Bancorp
Financing Receivable, Recorded Investment [Line Items]
Loans, net of deferred income			11,638
Substandard
Financing Receivable, Recorded Investment [Line Items]
Loans, net of deferred income		28,058	32,480
Substandard | Receivables Acquired with Deteriorated Credit Quality
Financing Receivable, Recorded Investment [Line Items]
Loans, net of deferred income		3,933	5,032
Substandard | Receivables Acquired with Deteriorated Credit Quality | River Valley Bancorp
Financing Receivable, Recorded Investment [Line Items]
Loans, net of deferred income			8,145
Doubtful
Financing Receivable, Recorded Investment [Line Items]
Loans, net of deferred income		0	0
Doubtful | Receivables Acquired with Deteriorated Credit Quality
Financing Receivable, Recorded Investment [Line Items]
Loans, net of deferred income		0	0
Doubtful | Receivables Acquired with Deteriorated Credit Quality | River Valley Bancorp
Financing Receivable, Recorded Investment [Line Items]
Loans, net of deferred income			0
Total
Financing Receivable, Recorded Investment [Line Items]
Loans, net of deferred income		1,657,699	1,623,514
Total | Receivables Acquired with Deteriorated Credit Quality
Financing Receivable, Recorded Investment [Line Items]
Loans, net of deferred income		8,532	10,050
Total | Receivables Acquired with Deteriorated Credit Quality | River Valley Bancorp
Financing Receivable, Recorded Investment [Line Items]
Loans, net of deferred income			195,698
Commercial and Industrial Loans and Leases
Financing Receivable, Recorded Investment [Line Items]
Loans, net of deferred income	[1]	468,965	458,538
Commercial and Industrial Loans and Leases | Receivables Acquired with Deteriorated Credit Quality
Financing Receivable, Recorded Investment [Line Items]
Loans, net of deferred income	[1]	1,247	1,656
Commercial and Industrial Loans and Leases | Pass
Financing Receivable, Recorded Investment [Line Items]
Loans, net of deferred income		449,772	437,353
Commercial and Industrial Loans and Leases | Special Mention
Financing Receivable, Recorded Investment [Line Items]
Loans, net of deferred income		8,792	10,454
Commercial and Industrial Loans and Leases | Substandard
Financing Receivable, Recorded Investment [Line Items]
Loans, net of deferred income		10,401	10,731
Commercial and Industrial Loans and Leases | Doubtful
Financing Receivable, Recorded Investment [Line Items]
Loans, net of deferred income		0	0
Commercial and Industrial Loans and Leases | Total
Financing Receivable, Recorded Investment [Line Items]
Loans, net of deferred income		468,965	458,538
Commercial Real Estate Loans
Financing Receivable, Recorded Investment [Line Items]
Loans, net of deferred income	[1]	871,970	858,030
Commercial Real Estate Loans | Receivables Acquired with Deteriorated Credit Quality
Financing Receivable, Recorded Investment [Line Items]
Loans, net of deferred income	[1]	6,602	7,688
Commercial Real Estate Loans | Pass
Financing Receivable, Recorded Investment [Line Items]
Loans, net of deferred income		833,572	814,033
Commercial Real Estate Loans | Special Mention
Financing Receivable, Recorded Investment [Line Items]
Loans, net of deferred income		23,865	26,549
Commercial Real Estate Loans | Substandard
Financing Receivable, Recorded Investment [Line Items]
Loans, net of deferred income		14,533	17,448
Commercial Real Estate Loans | Doubtful
Financing Receivable, Recorded Investment [Line Items]
Loans, net of deferred income		0	0
Commercial Real Estate Loans | Total
Financing Receivable, Recorded Investment [Line Items]
Loans, net of deferred income		871,970	858,030
Agricultural Loans
Financing Receivable, Recorded Investment [Line Items]
Loans, net of deferred income	[1]	316,764	306,946
Agricultural Loans | Receivables Acquired with Deteriorated Credit Quality
Financing Receivable, Recorded Investment [Line Items]
Loans, net of deferred income	[1]	683	706
Agricultural Loans | Pass
Financing Receivable, Recorded Investment [Line Items]
Loans, net of deferred income		287,410	287,975
Agricultural Loans | Special Mention
Financing Receivable, Recorded Investment [Line Items]
Loans, net of deferred income		26,230	14,670
Agricultural Loans | Substandard
Financing Receivable, Recorded Investment [Line Items]
Loans, net of deferred income		3,124	4,301
Agricultural Loans | Doubtful
Financing Receivable, Recorded Investment [Line Items]
Loans, net of deferred income		0	0
Agricultural Loans | Total
Financing Receivable, Recorded Investment [Line Items]
Loans, net of deferred income		$ 316,764	$ 306,946

[1] Total recorded investment in loans includes $7,623 in accrued interest.