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Note 7 - Loans and Related Allowance for Loan Losses - Additional Information on Impaired Loans (Details) - USD ($) $ in Thousands | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2017 | Jun. 30, 2016 | Jun. 30, 2017 | Jun. 30, 2016
Average recorded investment | $ 14,683 | $ 14,810 | $ 14,258 | $ 14,433
Interest income recognized | 181 | 198 | 375 | 395
Commercial And Industrial [Member] |  |  |  |
Average recorded investment | 2,228 | 1,110 | 1,889 | 1,343
Interest income recognized | 57 | 12 | 141 | 25
Real Estate Construction Porfolio Segment [Member] |  |  |  |
Average recorded investment | 676 | 1,368 | 877 | 1,508
Interest income recognized | 1 | 24 | 1 | 49
Real Estate Mortgage Portfolio Segment [Member] | Residential Loan [Member] |  |  |  |
Average recorded investment | 3,131 | 3,761 | 3,264 | 3,801
Interest income recognized | 28 | 37 | 50 | 73
Real Estate Mortgage Portfolio Segment [Member] | Commercial Loans [Member] |  |  |  |
Average recorded investment | 8,643 | 8,565 | 8,223 | 7,775
Interest income recognized | 95 | 125 | 183 | 248
Consumer Portfolio Segment [Member] |  |  |  |
Average recorded investment | 5 | 6 | 5 | 6
Interest income recognized |  |  |  |

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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=84173941&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=84173941&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=84173941&loc=d3e5212-111524 + Details
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