Allowance for Loan Losses and Credit Quality of Loans, Impaired Loans (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Allowance for Loan Losses and Credit Quality of Loans [Abstract]
Minimum balance for classified loans to be evaluated individually for impairment	$ 500
With an allowance recorded [Abstract]
Recorded investment balance (book)	27,168	$ 25,796
Unpaid principal balance (legal)	31,665	32,290
Related allowance	2,005	1,100
Average recorded investment	32,470	31,059	$ 23,317
Interest income recognized accrual	895	772	418
Originated Loans [Member]
With no allowance recorded [Abstract]
Recorded investment balance (book)	21,296	17,358
Unpaid principal balance (legal)	23,828	19,181
Originated Loans [Member] \| Commercial Loans [Member]
With no allowance recorded [Abstract]
Recorded investment balance (book)	7,586	8,316
Unpaid principal balance (legal)	8,606	9,189
With an allowance recorded [Abstract]
Recorded investment balance (book)	4,667	2,763
Unpaid principal balance (legal)	6,516	4,611
Related allowance	1,270	600
Originated Loans [Member] \| Commercial Loans [Member] \| Commercial [Member]
With no allowance recorded [Abstract]
Recorded investment balance (book)	2,244	1,748
Unpaid principal balance (legal)	2,490	1,901
With an allowance recorded [Abstract]
Recorded investment balance (book)	457	0
Unpaid principal balance (legal)	457	0
Related allowance	300	0
Average recorded investment	2,219	1,954	3,488
Interest income recognized accrual	71	115	0
Originated Loans [Member] \| Commercial Loans [Member] \| Commercial Real Estate [Member]
With no allowance recorded [Abstract]
Recorded investment balance (book)	3,165	4,505
Unpaid principal balance (legal)	3,175	4,520
With an allowance recorded [Abstract]
Recorded investment balance (book)	4,210	2,763
Unpaid principal balance (legal)	6,059	4,611
Related allowance	970	600
Average recorded investment	8,538	9,679	11,085
Interest income recognized accrual	164	169	95
Originated Loans [Member] \| Commercial Loans [Member] \| Agricultural [Member]
With no allowance recorded [Abstract]
Recorded investment balance (book)	576	20
Unpaid principal balance (legal)	1,164	26
With an allowance recorded [Abstract]
Average recorded investment	148	91	1,035
Interest income recognized accrual	1	1	1
Originated Loans [Member] \| Commercial Loans [Member] \| Agricultural Real Estate [Member]
With no allowance recorded [Abstract]
Recorded investment balance (book)	618	1,147
Unpaid principal balance (legal)	744	1,441
With an allowance recorded [Abstract]
Average recorded investment	628	1,346	1,067
Interest income recognized accrual	45	46	47
Originated Loans [Member] \| Commercial Loans [Member] \| Business Banking [Member]
With no allowance recorded [Abstract]
Recorded investment balance (book)	983	896
Unpaid principal balance (legal)	1,033	1,301
With an allowance recorded [Abstract]
Average recorded investment	960	610	127
Interest income recognized accrual	21	55	61
Originated Loans [Member] \| Consumer Loans [Member]
With no allowance recorded [Abstract]
Recorded investment balance (book)	7,693	5,498
Unpaid principal balance (legal)	8,595	6,033
Originated Loans [Member] \| Consumer Loans [Member] \| Indirect [Member]
With no allowance recorded [Abstract]
Recorded investment balance (book)	12	0
Unpaid principal balance (legal)	21	0
Originated Loans [Member] \| Consumer Loans [Member] \| Home Equity [Member]
With no allowance recorded [Abstract]
Recorded investment balance (book)	7,681	5,498
Unpaid principal balance (legal)	8,574	6,033
With an allowance recorded [Abstract]
Average recorded investment	7,070	5,198	3,120
Interest income recognized accrual	374	267	145
Originated Loans [Member] \| Residential Real Estate Mortgages [Member]
With no allowance recorded [Abstract]
Recorded investment balance (book)	6,017	3,544
Unpaid principal balance (legal)	6,627	3,959
With an allowance recorded [Abstract]
Average recorded investment	5,128	3,039	2,085
Interest income recognized accrual	219	119	69
Acquired Loans [Member] \| Commercial Loans [Member]
With no allowance recorded [Abstract]
Recorded investment balance (book)	0	2,666
Unpaid principal balance (legal)	0	3,830
Acquired Loans [Member] \| Commercial Loans [Member] \| Commercial [Member]
With an allowance recorded [Abstract]
Recorded investment balance (book)	1,205	3,009
Unpaid principal balance (legal)	1,321	4,668
Related allowance	735	500
Average recorded investment	2,045	5,756	0
Interest income recognized accrual	0	0	0
Acquired Loans [Member] \| Commercial Loans [Member] \| Commercial Real Estate [Member]
With no allowance recorded [Abstract]
Recorded investment balance (book)	0	2,666
Unpaid principal balance (legal)	0	3,830
With an allowance recorded [Abstract]
Average recorded investment	5,734	3,386	1,310
Interest income recognized accrual	$ 0	$ 0	$ 0

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The minimum balance for classified loans to be evaluated for impairment individually.

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Average amount of investment of impaired financing receivables with related allowance for credit losses and without a related allowance for credit losses.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 15
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=49124121&loc=d3e5212-111524

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 17
-URI http://asc.fasb.org/extlink&oid=49124121&loc=d3e5258-111524

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Amount of interest income recognized that the financing receivables (with related allowance for credit losses and without a related allowance for credit losses) were impaired.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 14A
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=49124121&loc=SL6953550-111524

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