Allowance for Loan Losses and Credit Quality of Loans, Impaired Loans (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 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)	34,213		34,213		$ 25,796
Unpaid principal balance (legal)	41,054		41,054		32,290
Related allowance	2,885		2,885		1,100
Average recorded investment	33,604	$ 32,027	33,363	$ 32,340
Interest income recognized accrual	241	151	425	284
Originated Loans [Member]
With no allowance recorded [Abstract]
Recorded investment balance (book)	19,664		19,664		17,358
Unpaid principal balance (legal)	21,272		21,272		19,181
With an allowance recorded [Abstract]
Recorded investment balance (book)	4,830		4,830		2,763
Unpaid principal balance (legal)	6,687		6,687		4,611
Related allowance	1,035		1,035		600
Average recorded investment	23,797	22,250	23,465	22,472
Interest income recognized accrual	241	151	425	284
Originated Loans [Member] \| Commercial Loans [Member]
With no allowance recorded [Abstract]
Recorded investment balance (book)	7,676		7,676		8,316
Unpaid principal balance (legal)	8,002		8,002		9,189
Originated Loans [Member] \| Commercial [Member]
With no allowance recorded [Abstract]
Recorded investment balance (book)	1,815		1,815		1,748
Unpaid principal balance (legal)	1,967		1,967		1,901
With an allowance recorded [Abstract]
Average recorded investment	1,768	2,013	1,742	2,025
Interest income recognized accrual	61	0	86	0
Originated Loans [Member] \| Commercial Real Estate [Member]
With no allowance recorded [Abstract]
Recorded investment balance (book)	4,205		4,205		4,505
Unpaid principal balance (legal)	4,216		4,216		4,520
With an allowance recorded [Abstract]
Average recorded investment	9,060	10,062	9,091	10,739
Interest income recognized accrual	41	42	82	84
Originated 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	123	19	124
Interest income recognized accrual	0	0	1	1
Originated Loans [Member] \| Agricultural Real Estate [Member]
With no allowance recorded [Abstract]
Recorded investment balance (book)	628		628		1,147
Unpaid principal balance (legal)	754		754		1,441
With an allowance recorded [Abstract]
Average recorded investment	630	1,412	633	1,418
Interest income recognized accrual	12	12	23	23
Originated Loans [Member] \| Business Banking [Member]
With no allowance recorded [Abstract]
Recorded investment balance (book)	1,009		1,009		896
Unpaid principal balance (legal)	1,040		1,040		1,301
With an allowance recorded [Abstract]
Average recorded investment	975	548	932	429
Interest income recognized accrual	2	11	6	23
Originated Loans [Member] \| Consumer Loans [Member]
With no allowance recorded [Abstract]
Recorded investment balance (book)	6,967		6,967		5,498
Unpaid principal balance (legal)	7,737		7,737		6,033
Originated Loans [Member] \| Indirect [Member]
With no allowance recorded [Abstract]
Recorded investment balance (book)	15		15		0
Unpaid principal balance (legal)	24		24		0
With an allowance recorded [Abstract]
Average recorded investment	16	0	11	0
Interest income recognized accrual	0	0	0	0
Originated Loans [Member] \| Home Equity [Member]
With no allowance recorded [Abstract]
Recorded investment balance (book)	6,952		6,952		5,498
Unpaid principal balance (legal)	7,713		7,713		6,033
With an allowance recorded [Abstract]
Average recorded investment	6,692	5,289	6,560	4,959
Interest income recognized accrual	92	60	164	103
Originated 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	1	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)	5,021		5,021		3,544
Unpaid principal balance (legal)	5,533		5,533		3,959
With an allowance recorded [Abstract]
Average recorded investment	4,636	2,803	4,476	2,778
Interest income recognized accrual	33	26	63	50
Acquired Loans [Member]
With an allowance recorded [Abstract]
Average recorded investment	9,807	9,777	9,898	9,868
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)	5,997		5,997		4,668
Related allowance	1,850		1,850		500
Acquired 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	2,602	6,315	2,722	6,375
Interest income recognized accrual	0	0	0	0
Acquired Loans [Member] \| Commercial Real Estate [Member]
With no allowance recorded [Abstract]
Recorded investment balance (book)	5,890		5,890		2,666
Unpaid principal balance (legal)	7,098		7,098		3,830
With an allowance recorded [Abstract]
Recorded investment balance (book)	1,321		1,321		0
Unpaid principal balance (legal)	1,329		1,329		0
Related allowance	850		850		$ 0
Average recorded investment	7,205	3,462	7,176	3,493
Interest income recognized accrual	$ 0	$ 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)

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-Publisher FASB

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