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Note 8 - Loans and Related Allowance for Loan and Lease Losses - Classes of the Loan Portfolio Summarized by Nonaccrual Loans and Still Accruing (Details) - USD ($) $ in Thousands | Mar. 31, 2018 | Dec. 31, 2017
--- | --- | ---
Loans, nonacrrual status | $ 8,747 | $ 8,433
Loans, 90+ days past due and accruing | 0 | 0
Commercial And Industrial [Member] |  |
Loans, nonacrrual status | 1,351 | 1,120
Loans, 90+ days past due and accruing | 0 | 0
Real Estate Construction Porfolio Segment [Member] |  |
Loans, nonacrrual status |  | 0
Loans, 90+ days past due and accruing | 0 | 0
Real Estate Mortgage Portfolio Segment [Member] | Residential Loan [Member] |  |
Loans, nonacrrual status | 3,934 | 4,002
Loans, 90+ days past due and accruing | 0 | 0
Real Estate Mortgage Portfolio Segment [Member] | Commercial Loans [Member] |  |
Loans, nonacrrual status | 3,462 | 3,311
Loans, 90+ days past due and accruing | 0 | 0
Consumer Portfolio Segment [Member] |  |
Loans, nonacrrual status |  | 0
Loans, 90+ days past due and accruing | $ 0 | $ 0

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- Definition Recorded investment in financing receivables that are 90 days or more past due and still accruing. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 7 -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=84173941&loc=d3e5111-111524 + Details
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- Definition Recorded investment in financing receivables that are on nonaccrual status as of the balance sheet date. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 7 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=84173941&loc=d3e5111-111524 + Details
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