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Note 8 - Loans and Related Allowance for Loan and Lease Losses (Details Textual) xbrli-pure in Thousands | 3 Months Ended | 6 Months Ended | 12 Months Ended |  |
--- | --- | --- | --- | --- | ---
Jun. 30, 2019 USD ($) | Mar. 31, 2019 USD ($) | Jun. 30, 2018 USD ($) | Jun. 30, 2019 USD ($) | Jun. 30, 2018 USD ($) | Dec. 31, 2018 USD ($) | Mar. 31, 2018 USD ($) | Dec. 31, 2017 USD ($)
Loans and Leases Receivable, Deferred Income, Total | $ 1,400,000 |  |  | $ 1,400,000 |  | $ 1,600,000 |  |
Financing Receivable, Troubled Debt Restructuring | 3,600,000 |  |  | $ 3,600,000 |  | 4,400,000 |  |
Number of Days Past Due |  |  |  | 90 days |  |  |  |
Loans and Leases Receivable, Impaired, Interest Lost on Nonaccrual Loans |  |  |  | $ 211,000 |  | 456,000 |  |
Allowance for Loan and Lease Losses, Write-offs | 98,000 |  | $ 315,000 | 613,000 | $ 329,000 |  |  |
Loans and Leases Receivable, Allowance, Ending Balance | $ 7,304,000 | $ 7,206,000 | $ 7,502,000 | $ 7,304,000 | $ 7,502,000 | 7,428,000 | $ 7,551,000 | $ 7,190,000
Financing Receivable, Troubled Debt Restructuring, Subsequent Default, Number of Contracts | 0 |  | 0 | 0 | 0 |  |  |
Commercial And Industrial [Member] |  |  |  |  |  |  |  |
Allowance for Loan and Lease Losses, Write-offs | $ 9,000 |  |  | $ 355,000 | $ 9,000 |  |  |
Loans and Leases Receivable, Allowance, Ending Balance | 539,000 | 586,000 | 1,180,000 | 539,000 | 1,180,000 | 969,000 | 1,256,000 | 999,000
Real Estate Construction Porfolio Segment [Member] |  |  |  |  |  |  |  |
Allowance for Loan and Lease Losses, Write-offs |  |  |  |  |  |  |  |
Loans and Leases Receivable, Allowance, Ending Balance | 90,000 | 748,000 | $ 89,000 | 90,000 | $ 89,000 | $ 100,000 | $ 92,000 | $ 313,000
Threshold For Loans Evaluated For Impairment [Member] |  |  |  |  |  |  |  |
Loans and Leases Receivable, before Fees, Gross | 500,000 |  |  | 500,000 |  |  |  |
Threshold For Loans Evaluated For Impairment [Member] | Outside Consultant [Member] |  |  |  |  |  |  |  |
Loans and Leases Receivable, before Fees, Gross | 250,000 |  |  | 250,000 |  |  |  |
Threshold For Loans Evaluated For Impairment [Member] | Criticized Relationships [Member] |  |  |  |  |  |  |  |
Financing Receivable, before Allowance for Credit Loss, Total | 150,000 |  |  | 150,000 |  |  |  |
Provision Fluctuation [Member] | Commercial And Industrial [Member] |  |  |  |  |  |  |  |
Allowance for Loan and Lease Losses, Write-offs |  | 336,000 |  |  |  |  |  |
Loans and Leases Receivable, Allowance, Ending Balance |  | $ 358,000 |  |  |  |  |  |
Provision Fluctuation [Member] | Real Estate Construction Porfolio Segment [Member] |  |  |  |  |  |  |  |
Allowance for Loan and Lease Losses, Adjustments, Other | $ 661,000 |  |  | $ 661,000 |  |  |  |

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- Definition Amount of other addition (reduction) in allowance reserve for credit loss. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 15 -URI http://asc.fasb.org/extlink&oid=118936363&loc=d3e5212-111524 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03.7(d)) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 + Details
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- Definition Amount of loans and leases that have been written off from both loan receivables and allowance reserve for credit loss. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 11B -Subparagraph (c)(3) -URI http://asc.fasb.org/extlink&oid=118936363&loc=SL6953423-111524 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03.7(d)) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 + Details
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- Definition Amount of allowance to cover probable credit losses on loans and leases. Includes carryover of or adjustments to the allowance for loan losses in connection with business combinations. Excludes allowance for loans and leases covered under loss sharing agreements. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03.7(d)) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 11B -Subparagraph (g) -URI http://asc.fasb.org/extlink&oid=118936363&loc=SL6953423-111524 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 30 -Section 50 -Paragraph 2 -Subparagraph (b)(1)(ii) -URI http://asc.fasb.org/extlink&oid=118939070&loc=d3e15032-111544 Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 11B -Subparagraph (c)(1) -URI http://asc.fasb.org/extlink&oid=118936363&loc=SL6953423-111524 Reference 5: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section S99 -Paragraph 4 -Subparagraph (SAB Topic 6.L.1) -URI http://asc.fasb.org/extlink&oid=27010918&loc=d3e74567-122707 + Details
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- Definition Amount, before allowance and fees, of loans and leases receivable. Excludes loans and leases covered under loss sharing agreements. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=118952595&loc=d3e4428-111522 + Details
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