Loans (Details 4) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Impaired financing receivables with related and not related allowances
Allowance average recorded Investment			$ 12,106
Allowance recorded Interest Income recognized			383
Allowance recorded cash basis interest recognized			383
Total average recorded investment	24,964	18,392
Total cash basis interest recognized	20	26
Total Interest Income Recognized	20	26
Commercial, industrial, and agricultural [Member]
Impaired financing receivables with related and not related allowances
Allowance average recorded Investment	3,083	3,711
Allowance recorded Interest Income recognized	4	3
Allowance recorded cash basis interest recognized	4	3
No allowance average recorded investment	3,217	2,050
No allowance recorded interest income recognized
No allowance recorded cash basis interest recognized
Commercial mortgages [Member]
Impaired financing receivables with related and not related allowances
Allowance average recorded Investment	5,504	6,412
Allowance recorded Interest Income recognized	3	19
Allowance recorded cash basis interest recognized	3	19
No allowance average recorded investment	12,723	6,040
No allowance recorded interest income recognized
No allowance recorded cash basis interest recognized
Residential real estate [Member]
Impaired financing receivables with related and not related allowances
Allowance average recorded Investment	334	179
Allowance recorded Interest Income recognized	13	4
Allowance recorded cash basis interest recognized	13	4
No allowance average recorded investment	103
No allowance recorded interest income recognized
No allowance recorded cash basis interest recognized

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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)

-URI http://asc.fasb.org/extlink&oid=7512638&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=7512638&loc=d3e5258-111524

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