Loans (Schedule of Risk Category of Loans) (Details) - USD ($) $ in Thousands		Mar. 31, 2017	Dec. 31, 2016
Financing Receivable, Recorded Investment [Line Items]
Loans, net of deferred income	[1]	$ 1,995,026	$ 2,001,415
Receivables Acquired with Deteriorated Credit Quality
Financing Receivable, Recorded Investment [Line Items]
Loans, net of deferred income		10,348	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		1,526,979	1,539,361
Pass | Receivables Acquired with Deteriorated Credit Quality
Financing Receivable, Recorded Investment [Line Items]
Loans, net of deferred income		1,489	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		57,342	51,673
Special Mention | Receivables Acquired with Deteriorated Credit Quality
Financing Receivable, Recorded Investment [Line Items]
Loans, net of deferred income		3,121	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		31,571	32,480
Substandard | Receivables Acquired with Deteriorated Credit Quality
Financing Receivable, Recorded Investment [Line Items]
Loans, net of deferred income		4,755	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		1,615,892	1,623,514
Total | Receivables Acquired with Deteriorated Credit Quality
Financing Receivable, Recorded Investment [Line Items]
Loans, net of deferred income		9,365	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]	451,677	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		1,251	1,656
Commercial and Industrial Loans and Leases | Pass
Financing Receivable, Recorded Investment [Line Items]
Loans, net of deferred income		432,133	437,353
Commercial and Industrial Loans and Leases | Special Mention
Financing Receivable, Recorded Investment [Line Items]
Loans, net of deferred income		9,119	10,454
Commercial and Industrial Loans and Leases | Substandard
Financing Receivable, Recorded Investment [Line Items]
Loans, net of deferred income		10,425	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		451,677	458,538
Commercial Real Estate Loans
Financing Receivable, Recorded Investment [Line Items]
Loans, net of deferred income	[1]	867,635	858,030
Commercial Real Estate Loans | Receivables Acquired with Deteriorated Credit Quality
Financing Receivable, Recorded Investment [Line Items]
Loans, net of deferred income		7,426	7,688
Commercial Real Estate Loans | Pass
Financing Receivable, Recorded Investment [Line Items]
Loans, net of deferred income		824,473	814,033
Commercial Real Estate Loans | Special Mention
Financing Receivable, Recorded Investment [Line Items]
Loans, net of deferred income		25,355	26,549
Commercial Real Estate Loans | Substandard
Financing Receivable, Recorded Investment [Line Items]
Loans, net of deferred income		17,807	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		867,635	858,030
Agricultural Loans
Financing Receivable, Recorded Investment [Line Items]
Loans, net of deferred income	[1]	296,580	306,946
Agricultural Loans | Receivables Acquired with Deteriorated Credit Quality
Financing Receivable, Recorded Investment [Line Items]
Loans, net of deferred income		688	706
Agricultural Loans | Pass
Financing Receivable, Recorded Investment [Line Items]
Loans, net of deferred income		270,373	287,975
Agricultural Loans | Special Mention
Financing Receivable, Recorded Investment [Line Items]
Loans, net of deferred income		22,868	14,670
Agricultural Loans | Substandard
Financing Receivable, Recorded Investment [Line Items]
Loans, net of deferred income		3,339	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		$ 296,580	$ 306,946

[1] Total recorded investment in loans includes $8,097 in accrued interest.