Allowance for Loan Losses and Credit Quality of Loans, Impaired Loans (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014	Dec. 31, 2014
Allowance for Loan Losses and Credit Quality of Loans [Abstract]
Minimum balance for classified loans to be evaluated individually for impairment	$ 500		$ 500
With an allowance recorded [Abstract]
Recorded investment balance (book)	35,333		35,333		$ 25,796
Unpaid principal balance (legal)	41,334		41,334		32,290
Related allowance	3,545		3,545		1,100
Average recorded investment	35,142	$ 31,705	33,980	$ 32,162
Interest income recognized accrual	269	179	694	463
Originated Loans [Member]
With no allowance recorded [Abstract]
Recorded investment balance (book)	19,975		19,975		17,358
Unpaid principal balance (legal)	21,644		21,644		19,181
With an allowance recorded [Abstract]
Average recorded investment	25,693	22,146	24,252	22,398
Interest income recognized accrual	269	179	694	463
Originated Loans [Member] \| Commercial Loans [Member]
With no allowance recorded [Abstract]
Recorded investment balance (book)	6,518		6,518		8,316
Unpaid principal balance (legal)	6,855		6,855		9,189
With an allowance recorded [Abstract]
Recorded investment balance (book)	6,041		6,041		2,763
Unpaid principal balance (legal)	7,912		7,912		4,611
Related allowance	1,695		1,695		600
Originated Loans [Member] \| Commercial Loans [Member] \| Commercial [Member]
With no allowance recorded [Abstract]
Recorded investment balance (book)	1,694		1,694		1,748
Unpaid principal balance (legal)	1,846		1,846		1,901
With an allowance recorded [Abstract]
Recorded investment balance (book)	948		948		0
Unpaid principal balance (legal)	953		953		0
Related allowance	300		300		0
Average recorded investment	2,469	1,957	2,026	2,001
Interest income recognized accrual	42	0	128	0
Originated Loans [Member] \| Commercial Loans [Member] \| Commercial Real Estate [Member]
With no allowance recorded [Abstract]
Recorded investment balance (book)	3,187		3,187		4,505
Unpaid principal balance (legal)	3,198		3,198		4,520
With an allowance recorded [Abstract]
Recorded investment balance (book)	5,093		5,093		2,763
Unpaid principal balance (legal)	6,959		6,959		4,611
Related allowance	1,395		1,395		600
Average recorded investment	8,560	9,619	8,884	10,400
Interest income recognized accrual	42	43	124	127
Originated Loans [Member] \| Commercial Loans [Member] \| Agricultural [Member]
With no allowance recorded [Abstract]
Recorded investment balance (book)	19		19		20
Unpaid principal balance (legal)	25		25		26
With an allowance recorded [Abstract]
Average recorded investment	19	102	19	115
Interest income recognized accrual	0	0	1	1
Originated Loans [Member] \| Commercial Loans [Member] \| Agricultural Real Estate [Member]
With no allowance recorded [Abstract]
Recorded investment balance (book)	623		623		1,147
Unpaid principal balance (legal)	749		749		1,441
With an allowance recorded [Abstract]
Average recorded investment	626	1,395	630	1,410
Interest income recognized accrual	11	12	34	35
Originated Loans [Member] \| Commercial Loans [Member] \| Business Banking [Member]
With no allowance recorded [Abstract]
Recorded investment balance (book)	995		995		896
Unpaid principal balance (legal)	1,037		1,037		1,301
With an allowance recorded [Abstract]
Average recorded investment	1,003	677	952	509
Interest income recognized accrual	3	10	9	33
Originated Loans [Member] \| Consumer Loans [Member]
With no allowance recorded [Abstract]
Recorded investment balance (book)	7,590		7,590		5,498
Unpaid principal balance (legal)	8,403		8,403		6,033
Originated Loans [Member] \| Consumer Loans [Member] \| Indirect [Member]
With no allowance recorded [Abstract]
Recorded investment balance (book)	13		13		0
Unpaid principal balance (legal)	23		23		0
With an allowance recorded [Abstract]
Average recorded investment	20	0	14	0
Interest income recognized accrual	0	0	0	0
Originated Loans [Member] \| Consumer Loans [Member] \| Home Equity [Member]
With no allowance recorded [Abstract]
Recorded investment balance (book)	7,577		7,577		5,498
Unpaid principal balance (legal)	8,380		8,380		6,033
With an allowance recorded [Abstract]
Average recorded investment	7,432	5,435	6,869	5,099
Interest income recognized accrual	134	85	298	188
Originated Loans [Member] \| Consumer Loans [Member] \| Direct [Member]
With no allowance recorded [Abstract]
Recorded investment balance (book)	0		0		0
Unpaid principal balance (legal)	0		0		0
With an allowance recorded [Abstract]
Average recorded investment	0	0	1	0
Interest income recognized accrual	0	0	0	0
Originated Loans [Member] \| Residential Real Estate Mortgages [Member]
With no allowance recorded [Abstract]
Recorded investment balance (book)	5,867		5,867		3,544
Unpaid principal balance (legal)	6,386		6,386		3,959
With an allowance recorded [Abstract]
Average recorded investment	5,564	2,961	4,857	2,864
Interest income recognized accrual	37	29	100	79
Acquired Loans [Member]
With an allowance recorded [Abstract]
Average recorded investment	9,449	9,559	9,728	9,764
Interest income recognized accrual	0	0	0	0
Acquired Loans [Member] \| Commercial Loans [Member]
With an allowance recorded [Abstract]
Recorded investment balance (book)	3,829		3,829		3,009
Unpaid principal balance (legal)	5,989		5,989		4,668
Related allowance	1,850		1,850		500
Acquired Loans [Member] \| Commercial Loans [Member] \| Commercial [Member]
With an allowance recorded [Abstract]
Recorded investment balance (book)	2,508		2,508		3,009
Unpaid principal balance (legal)	4,668		4,668		4,668
Related allowance	1,000		1,000		500
Average recorded investment	2,531	6,161	2,658	6,303
Interest income recognized accrual	0	0	0	0
Acquired Loans [Member] \| Commercial Loans [Member] \| Commercial Real Estate [Member]
With no allowance recorded [Abstract]
Recorded investment balance (book)	5,488		5,488		2,666
Unpaid principal balance (legal)	5,789		5,789		3,830
With an allowance recorded [Abstract]
Recorded investment balance (book)	1,321		1,321		0
Unpaid principal balance (legal)	1,321		1,321		0
Related allowance	850		850		$ 0
Average recorded investment	6,918	3,398	7,070	3,461
Interest income recognized accrual	$ 0	$ 0	$ 0	$ 0

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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.

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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 15

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