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Note 6 - Loans And Related Allowance For Loan Losses (Detail) - Additional Information on Impaired Loans (USD $) In Thousands, unless otherwise specified | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2012 | Sep. 30, 2011 | Sep. 30, 2012 | Sep. 30, 2011
Commercial and Industrial [Member] |  |  |  |
Total: |  |  |  |
Average Recorded Investment | $ 2,535 | $ 3,295 | $ 2,170 | $ 3,266
Interest Income Recognized | 139 | 11 | 170 | 93
Real Estate Construction [Member] |  |  |  |
Total: |  |  |  |
Average Recorded Investment | 2,305 | 630 | 2,400 | 624
Interest Income Recognized |  | 15 | 113 | 15
Residential Real Estate Mortgage [Member] |  |  |  |
Total: |  |  |  |
Average Recorded Investment | 3,622 | 997 | 3,764 | 793
Interest Income Recognized | 85 | 23 | 169 | 68
Commercial Real Estate Mortgage [Member] |  |  |  |
Total: |  |  |  |
Average Recorded Investment | 3,597 | 4,899 | 3,985 | 4,081
Interest Income Recognized | 200 | 86 | 324 | 188
Consumer Installment [Member] |  |  |  |
Total: |  |  |  |
Average Recorded Investment | 13 | 25 | 27 | 13
Interest Income Recognized | $ 1 |  | $ 2 | $ 4

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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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