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Note 7 - Loans And Related Allowance For Loan Losses (Detail) - Additional Information on Impaired Loans (USD $) In Thousands, unless otherwise specified | 3 Months Ended
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Mar. 31, 2013 | Mar. 31, 2012
Commercial and Industrial [Member] |  |
Total: |  |
Impaired loans, average recorded investment | $ 2,975 | $ 1,781
Impaired loans, interest income recognized | 55 | 12
Real Estate Construction [Member] |  |
Total: |  |
Impaired loans, average recorded investment | 3,772 | 471
Impaired loans, interest income recognized | 37 | 1
Residential Real Estate Mortgage [Member] |  |
Total: |  |
Impaired loans, average recorded investment | 5,642 | 2,809
Impaired loans, interest income recognized | 74 | 27
Commercial Real Estate Mortgage [Member] |  |
Total: |  |
Impaired loans, average recorded investment | 6,832 | 1,884
Impaired loans, interest income recognized | 110 | 26
Consumer Installment [Member] |  |
Total: |  |
Impaired loans, average recorded investment | 18 | 28
Impaired loans, interest income recognized |  | $ 1

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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=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 + Details
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- Definition 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. + 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)(2) -URI http://asc.fasb.org/extlink&oid=7512638&loc=d3e5212-111524 + Details
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