Allowance for Loan Losses and Credit Quality of Loans, Impaired Loans (Details) (USD $)	3 Months Ended
Mar. 31, 2015	Mar. 31, 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	$ 500,000
With an allowance recorded [Abstract]
Recorded investment balance (book)	32,717,000		25,796,000
Unpaid principal balance (legal)	39,371,000		32,290,000
Related allowance	2,950,000		1,100,000
Average recorded investment	33,026,000	32,294,000
Interest income recognized accrual	183,000	132,000
Originated Loans [Member]
With no allowance recorded [Abstract]
Recorded investment balance (book)	18,068,000		17,358,000
Unpaid principal balance (legal)	19,540,000		19,181,000
With an allowance recorded [Abstract]
Recorded investment balance (book)	4,877,000		2,763,000
Unpaid principal balance (legal)	6,725,000		4,611,000
Related allowance	1,100,000		600,000
Average recorded investment	23,007,000	22,334,000
Interest income recognized accrual	183,000	132,000
Originated Loans [Member] \| Commercial Loans [Member]
With no allowance recorded [Abstract]
Recorded investment balance (book)	7,376,000		8,316,000
Unpaid principal balance (legal)	7,713,000		9,189,000
Originated Loans [Member] \| Commercial [Member]
With no allowance recorded [Abstract]
Recorded investment balance (book)	1,628,000		1,748,000
Unpaid principal balance (legal)	1,781,000		1,901,000
With an allowance recorded [Abstract]
Average recorded investment	1,689,000	2,038,000
Interest income recognized accrual	25,000	0
Originated Loans [Member] \| Commercial Real Estate [Member]
With no allowance recorded [Abstract]
Recorded investment balance (book)	4,227,000		4,505,000
Unpaid principal balance (legal)	4,238,000		4,520,000
With an allowance recorded [Abstract]
Average recorded investment	9,125,000	11,553,000
Interest income recognized accrual	41,000	42,000
Originated Loans [Member] \| Agricultural [Member]
With no allowance recorded [Abstract]
Recorded investment balance (book)	19,000		20,000
Unpaid principal balance (legal)	25,000		26,000
With an allowance recorded [Abstract]
Average recorded investment	20,000	125,000
Interest income recognized accrual	0	0
Originated Loans [Member] \| Agricultural Real Estate [Member]
With no allowance recorded [Abstract]
Recorded investment balance (book)	633,000		1,147,000
Unpaid principal balance (legal)	759,000		1,441,000
With an allowance recorded [Abstract]
Average recorded investment	636,000	1,424,000
Interest income recognized accrual	11,000	12,000
Originated Loans [Member] \| Business Banking [Member]
With no allowance recorded [Abstract]
Recorded investment balance (book)	869,000		896,000
Unpaid principal balance (legal)	910,000		1,301,000
With an allowance recorded [Abstract]
Average recorded investment	873,000	185,000
Interest income recognized accrual	4,000	12,000
Originated Loans [Member] \| Consumer Loans [Member]
With no allowance recorded [Abstract]
Recorded investment balance (book)	6,423,000		5,498,000
Unpaid principal balance (legal)	7,085,000		6,033,000
Originated Loans [Member] \| Indirect [Member]
With no allowance recorded [Abstract]
Recorded investment balance (book)	17,000		0
Unpaid principal balance (legal)	26,000		0
With an allowance recorded [Abstract]
Average recorded investment	9,000	0
Interest income recognized accrual	0	0
Originated Loans [Member] \| Home Equity [Member]
With no allowance recorded [Abstract]
Recorded investment balance (book)	6,403,000		5,498,000
Unpaid principal balance (legal)	7,056,000		6,033,000
With an allowance recorded [Abstract]
Average recorded investment	6,388,000	4,282,000
Interest income recognized accrual	72,000	43,000
Originated Loans [Member] \| Direct [Member]
With no allowance recorded [Abstract]
Recorded investment balance (book)	3,000		0
Unpaid principal balance (legal)	3,000		0
With an allowance recorded [Abstract]
Average recorded investment	2,000	0
Interest income recognized accrual	0	0
Originated Loans [Member] \| Residential Real Estate Mortgages [Member]
With no allowance recorded [Abstract]
Recorded investment balance (book)	4,269,000		3,544,000
Unpaid principal balance (legal)	4,742,000		3,959,000
With an allowance recorded [Abstract]
Average recorded investment	4,265,000	2,727,000
Interest income recognized accrual	30,000	23,000
Acquired Loans [Member]
With an allowance recorded [Abstract]
Average recorded investment	10,019,000	9,960,000
Interest income recognized accrual	0	0
Acquired Loans [Member] \| Commercial Loans [Member]
With an allowance recorded [Abstract]
Recorded investment balance (book)	3,837,000		3,009,000
Unpaid principal balance (legal)	5,997,000		4,668,000
Related allowance	1,850,000		500,000
Acquired Loans [Member] \| Commercial [Member]
With an allowance recorded [Abstract]
Recorded investment balance (book)	2,508,000		3,009,000
Unpaid principal balance (legal)	4,668,000		4,668,000
Related allowance	1,000,000		500,000
Average recorded investment	2,883,000	6,436,000
Interest income recognized accrual	0	0
Acquired Loans [Member] \| Commercial Real Estate [Member]
With no allowance recorded [Abstract]
Recorded investment balance (book)	5,935,000		2,666,000
Unpaid principal balance (legal)	7,109,000		3,830,000
With an allowance recorded [Abstract]
Recorded investment balance (book)	1,329,000		0
Unpaid principal balance (legal)	1,329,000		0
Related allowance	850,000		0
Average recorded investment	7,136,000	3,524,000
Interest income recognized accrual	$ 0	$ 0

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

+ References

No definition available.

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- Definition

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=35738203&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=35738203&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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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 14A

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=35738203&loc=SL6953550-111524

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Amount of allowance for credit losses related to recorded investment.

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Amount of unpaid principal balance of impaired financing receivables with related allowance for credit losses and without related allowance for credit losses.

+ References

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Amount of investment in impaired financing receivables for which there is no related allowance for credit losses.

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Amount of unpaid principal balance of impaired financing receivables for which there is no related allowance for credit losses.

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Amount of investment in impaired financing receivables for which there is a related allowance for credit losses.

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Unpaid principal balance of impaired financing receivables for which there is a related allowance for credit losses.

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