Loans (Details 1) (USD $) In Thousands, unless otherwise specified	3 Months Ended
Mar. 31, 2013	Mar. 31, 2012
Allowance for loan losses
Allowance for loan losses, Beginning Balance	$ 14,060	$ 12,615
Charge-offs	(1,169)	(769)
Recoveries	76	65
Provision (benefit) for loan losses	930	1,104
Allowance for loan losses, Ending Balance	13,897	13,015
Commercial, Industrial, and Agricultural [Member]
Allowance for loan losses
Allowance for loan losses, Beginning Balance	4,940	4,511
Charge-offs	0	(225)
Recoveries	0	3
Provision (benefit) for loan losses	331	653
Allowance for loan losses, Ending Balance	5,271	4,942
Commercial Mortgages [Member]
Allowance for loan losses
Allowance for loan losses, Beginning Balance	4,697	4,470
Charge-offs	(607)	(115)
Recoveries	1
Provision (benefit) for loan losses	208	22
Allowance for loan losses, Ending Balance	4,299	4,377
Residential real estate [Member]
Allowance for loan losses
Allowance for loan losses, Beginning Balance	2,466	1,991
Charge-offs	(172)	(87)
Recoveries	1
Provision (benefit) for loan losses	100	93
Allowance for loan losses, Ending Balance	2,395	1,997
Consumer [Member]
Allowance for loan losses
Allowance for loan losses, Beginning Balance	1,699	1,404
Charge-offs	(331)	(256)
Recoveries	41	27
Provision (benefit) for loan losses	298	260
Allowance for loan losses, Ending Balance	1,707	1,435
Credit cards [Member]
Allowance for loan losses
Allowance for loan losses, Beginning Balance	83	71
Charge-offs	(12)	(19)
Recoveries	2	1
Provision (benefit) for loan losses	4	43
Allowance for loan losses, Ending Balance	77	96
Overdrafts [Member]
Allowance for loan losses
Allowance for loan losses, Beginning Balance	175	168
Charge-offs	(47)	(67)
Recoveries	31	34
Provision (benefit) for loan losses	(11)	33
Allowance for loan losses, Ending Balance	$ 148	$ 168

A valuation allowance for financing receivables that are expected to be uncollectible.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 11B

-Subparagraph (c)(1)

-URI http://asc.fasb.org/extlink&oid=7512638&loc=SL6953423-111524

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- Definition

Amount of recovery of financing receivables doubtful of collection that were previously charged off.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 11B

-Subparagraph (c)(4)

-URI http://asc.fasb.org/extlink&oid=7512638&loc=SL6953423-111524

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- Definition

Amount of direct write-downs of financing receivables charged against the allowance.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 11B

-Subparagraph (c)(3)

-URI http://asc.fasb.org/extlink&oid=7512638&loc=SL6953423-111524

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- Definition

The sum of the periodic provision charged to earnings, based on an assessment of uncollectibility from the counterparty on account of loan, lease or other credit losses, to reduce these accounts to the amount that approximates their net realizable value.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

-Paragraph 11

-Article 9

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 11B

-Subparagraph (c)(2)

-URI http://asc.fasb.org/extlink&oid=7512638&loc=SL6953423-111524

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 95

-Paragraph 28

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher AICPA

-Name Audit and Accounting Guide (AAG)

-Number AAG-DEP

-Paragraph 168, 169, 170

-IssueDate 2006-05-01

-Chapter 5

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 5: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 28

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=6943989&loc=d3e3602-108585

Reference 6: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 225

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-04.11)

-URI http://asc.fasb.org/extlink&oid=6879574&loc=d3e536633-122882

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