Loans (Details 1) (USD $) In Thousands, unless otherwise specified	3 Months Ended	6 Months Ended
Jun. 30, 2012	Jun. 30, 2011	Jun. 30, 2012	Jun. 30, 2011	Jun. 30, 2012	Jun. 30, 2011
Allowance for loan losses
Allowance for loan losses, Beginning Balance	$ 13,015	$ 11,224	$ 12,615	$ 10,820	$ 13,690	$ 11,715
Charge-offs	(1,126)	(548)	(1,895)	(982)
Recoveries	55	47	120	108
Provision for loan losses	1,746	992	2,850	1,769
Commercial industrial and agricultural [Member]
Allowance for loan losses
Allowance for loan losses, Beginning Balance	4,942	3,732	4,511	3,517	5,115	3,770
Charge-offs	(422)	(173)	(647)	(215)
Recoveries	5	3	8	4
Provision for loan losses	590	208	1,243	464
Commercial mortgages [Member]
Allowance for loan losses
Allowance for loan losses, Beginning Balance	4,377	3,879	4,470	3,511	4,553	4,399
Charge-offs	(121)	(41)	(236)	(88)
Recoveries	0	0	0	0
Provision for loan losses	297	561	319	976
Residential real estate [Member]
Allowance for loan losses
Allowance for loan losses, Beginning Balance	1,997	1,879	1,991	1,916	2,225	1,900
Charge-offs	(137)	(63)	(224)	(77)
Recoveries	0	0	0	0
Provision for loan losses	365	84	458	61
Consumer [Member]
Allowance for loan losses
Allowance for loan losses, Beginning Balance	1,435	1,507	1,404	1,561	1,568	1,400
Charge-offs	(382)	(202)	(638)	(462)
Recoveries	22	21	49	45
Provision for loan losses	493	74	753	256
Credit cards [Member]
Allowance for loan losses
Allowance for loan losses, Beginning Balance	96	96	71	96	81	104
Charge-offs	(14)	(7)	(33)	(25)
Recoveries	6	3	7	5
Provision for loan losses	(7)	12	36	28
Overdrafts [Member]
Allowance for loan losses
Allowance for loan losses, Beginning Balance	168	131	168	219	148	142
Charge-offs	(50)	(62)	(117)	(115)
Recoveries	22	20	56	54
Provision for loan losses	$ 8	$ 53	$ 41	$ (16)

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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