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Note 7 - Loans and Related Allowance for Loan and Lease Losses - Impaired Loans by Class (Details) - USD ($) $ in Thousands | Sep. 30, 2016 | Dec. 31, 2015
--- | --- | ---
Commercial And Industrial [Member] |  |
Recorded investment, with no related allowance | $ 569 | $ 1,027
Unpaid principal balance, with no related allowance | 569 | 1,025
Recorded investment, with related allowance | 275 | 781
Unpaid principal balance, with related allowance | 275 | 781
Related allowance | 184 | 388
Recorded investment | 844 | 1,808
Unpaid principal balance | 844 | 1,806
Real Estate Construction Porfolio Segment [Member] | Residential Loan [Member] |  |
Recorded investment, with related allowance | 464 |
Unpaid principal balance, with related allowance | 462 |
Related allowance | 104 |
Real Estate Construction Porfolio Segment [Member] |  |
Recorded investment, with no related allowance | 1,076 | 1,657
Unpaid principal balance, with no related allowance | 1,076 | 1,651
Recorded investment, with related allowance | 17 | 130
Unpaid principal balance, with related allowance | 17 | 130
Related allowance | 17 | 130
Recorded investment | 1,093 | 1,787
Unpaid principal balance | 1,093 | 1,781
Real Estate Mortgage Portfolio Segment [Member] | Residential Loan [Member] |  |
Recorded investment, with no related allowance | 2,774 | 2,445
Unpaid principal balance, with no related allowance | 2,771 | 2,443
Recorded investment, with related allowance |  | 1,436
Unpaid principal balance, with related allowance |  | 1,436
Related allowance | 104 | 276
Recorded investment | 3,238 | 3,881
Unpaid principal balance | 3,233 | 3,879
Real Estate Mortgage Portfolio Segment [Member] | Commercial Loans [Member] |  |
Recorded investment, with no related allowance | 1,378 | 2,337
Unpaid principal balance, with no related allowance | 1,375 | 2,335
Recorded investment, with related allowance |  | 3,862
Unpaid principal balance, with related allowance |  | 3,846
Related allowance | 239 | 39
Recorded investment | 6,466 | 6,199
Unpaid principal balance | 6,453 | 6,181
Consumer Portfolio Segment [Member] |  |
Recorded investment, with no related allowance | 5 | 6
Unpaid principal balance, with no related allowance | 5 | 6
Recorded investment, with related allowance |  |
Unpaid principal balance, with related allowance |  |
Related allowance |  |
Recorded investment | 5 | 6
Unpaid principal balance | 5 | 6
Commercial Loans [Member] |  |
Recorded investment, with related allowance | 5,088 |
Unpaid principal balance, with related allowance | 5,078 |
Related allowance | 239 |
Recorded investment, with no related allowance | 5,797 | 7,466
Unpaid principal balance, with no related allowance | 5,791 | 7,454
Recorded investment, with related allowance | 5,849 | 6,215
Unpaid principal balance, with related allowance | 5,837 | 6,199
Related allowance | 544 | 833
Recorded investment | 11,646 | 13,681
Unpaid principal balance | $ 11,628 | $ 13,653

X
- Definition 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 14A -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=66008989&loc=SL6953550-111524 + Details
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X
- Definition Amount of allowance for credit losses related to recorded investment. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Recorded Investment -URI http://asc.fasb.org/extlink&oid=65880944 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 15 -Subparagraph (a)(3) -URI http://asc.fasb.org/extlink&oid=66008989&loc=d3e5212-111524 + Details
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- Definition Amount of unpaid principal balance of impaired financing receivables with related allowance for credit losses and without 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 (a)(4) -URI http://asc.fasb.org/extlink&oid=66008989&loc=d3e5212-111524 + Details
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- Definition Amount of investment in impaired financing receivables for which there is no 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 14A -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=66008989&loc=SL6953550-111524 + Details
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