Loans (Details 1) (USD $) In Thousands, unless otherwise specified	3 Months Ended	9 Months Ended
Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2012	Sep. 30, 2011
Allowance for loan losses
Allowance for loan losses, Beginning Balance	$ 13,690	$ 11,715	$ 12,615	$ 10,820
Charge-offs	(1,277)	(434)	(3,172)	(1,416)
Recoveries	48	67	168	175
Provision (benefit) for loan losses	1,188	904	4,038	2,673
Allowance for loan losses, Ending Balance	13,649	12,252	13,649	12,252
Commercial, Industrial, and Agricultural [Member]
Allowance for loan losses
Allowance for loan losses, Beginning Balance	5,115	3,770	4,511	3,517
Charge-offs	(751)	(84)	(1,398)	(299)
Recoveries	6	3	14	7
Provision (benefit) for loan losses	103	33	1,346	497
Allowance for loan losses, Ending Balance	4,473	3,722	4,473	3,722
Commercial Mortgages [Member]
Allowance for loan losses
Allowance for loan losses, Beginning Balance	4,553	4,399	4,470	3,511
Charge-offs	(165)	(12)	(401)	(100)
Recoveries	0		0
Provision (benefit) for loan losses	504	467	823	1,443
Allowance for loan losses, Ending Balance	4,892	4,854	4,892	4,854
Residential real estate [Member]
Allowance for loan losses
Allowance for loan losses, Beginning Balance	2,225	1,900	1,991	1,916
Charge-offs	(7)	(55)	(231)	(132)
Recoveries	1	12	1	12
Provision (benefit) for loan losses	113	154	571	215
Allowance for loan losses, Ending Balance	2,332	2,011	2,332	2,011
Consumer [Member]
Allowance for loan losses
Allowance for loan losses, Beginning Balance	1,568	1,400	1,404	1,561
Charge-offs	(252)	(221)	(890)	(683)
Recoveries	18	31	67	76
Provision (benefit) for loan losses	372	202	1,125	458
Allowance for loan losses, Ending Balance	1,706	1,412	1,706	1,412
Credit cards [Member]
Allowance for loan losses
Allowance for loan losses, Beginning Balance	81	104	71	96
Charge-offs	(22)	(12)	(55)	(37)
Recoveries	1	3	8	8
Provision (benefit) for loan losses	19	2	55	30
Allowance for loan losses, Ending Balance	79	97	79	97
Overdrafts [Member]
Allowance for loan losses
Allowance for loan losses, Beginning Balance	148	142	168	219
Charge-offs	(80)	(50)	(197)	(165)
Recoveries	22	18	78	72
Provision (benefit) for loan losses	77	46	118	30
Allowance for loan losses, Ending Balance	$ 167	$ 156	$ 167	$ 156

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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