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Note 5 - Loans and Related Allowance for Loan and Lease Losses (Details Textual) | 3 Months Ended | 12 Months Ended
--- | --- | ---
Mar. 31, 2018 | Dec. 31, 2019 USD ($) | Dec. 31, 2018 USD ($) | Dec. 31, 2017
Loans and Leases Receivable, Deferred Income, Total |  | $ 1,300,000 | $ 1,600,000 |
Financing Receivable, Troubled Debt Restructuring |  | 3,600,000 | 4,400,000 |
Financing Receivable, Allowance for Credit Loss, Writeoff |  | 33,000 | $ 459,000 |
Financing Receivable, Troubled Debt Restructuring, Subsequent Default |  | $ 36,000 |  |
Financing Receivable, Troubled Debt Restructuring, Subsequent Default, Number of Contracts |  | 0 | 0 |
Number of Days Past Due |  | 90 days |  |
Loans and Leases Receivable, Impaired, Interest Lost on Nonaccrual Loans |  | $ 342,000 | $ 456,000 |
Allowance for Loan and Lease Losses, Write-offs |  | 1,809,000 | 1,118,000 |
Commercial And Industrial [Member] |  |  |  |
Allowance for Loan and Lease Losses, Write-offs |  | 519,000 | 610,000 |
Consumer Portfolio Segment [Member] |  |  |  |
Allowance for Loan and Lease Losses, Write-offs |  | 735,000 | 220,000 |
Real Estate Construction Porfolio Segment [Member] |  |  |  |
Allowance for Loan and Lease Losses, Write-offs |  |  |  |
Loans and Leases Receivable, Historical Loss Rate | (0.127%) |  |  | 0.775%
Threshold For Loans Evaluated For Impairment [Member] |  |  |  |
Loans and Leases Receivable, before Fees, Gross |  | 500,000 |  |
Threshold For Loans Evaluated For Impairment [Member] | Outside Consultant [Member] |  |  |  |
Loans and Leases Receivable, before Fees, Gross |  | 250,000 |  |
Threshold For Loans Evaluated For Impairment [Member] | Criticized Relationships [Member] |  |  |  |
Loans and Leases Receivable, before Fees, Gross |  | 125,000 |  |
Provision Fluctuation [Member] | Commercial And Industrial [Member] |  |  |  |
Allowance for Loan and Lease Losses, Write-offs |  | 438,000 |  |
Provision Fluctuation [Member] | Real Estate Mortgage Portfolio Segment [Member] |  |  |  |
Allowance for Loan and Lease Losses, Write-offs |  | 360,000 |  |
Provision Fluctuation [Member] | Consumer Portfolio Segment [Member] |  |  |  |
Allowance for Loan and Lease Losses, Write-offs |  | $ 566,000 |  |

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- Definition Represents the historical loss rate for loans and leases held in portfolio, including but not limited to, commercial and consumer loans. + References No definition available. + Details
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- Definition The number of days past due. + References No definition available. + 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 writeoff of financing receivable, charged against allowance for credit loss. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 20 -Section 50 -Paragraph 13 -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=119407570&loc=SL82919249-210447 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 (c)(3) -URI http://asc.fasb.org/extlink&oid=118936363&loc=SL6953423-111524 Reference 3: http://www.xbrl.org/2003/role/exampleRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 20 -Section 55 -Paragraph 79 -URI http://asc.fasb.org/extlink&oid=118955255&loc=SL82922352-210448 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -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, 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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- Definition Amount of deferred interest and fee income, unamortized costs incurred to originate loans and leases, unamortized loan commitments and loan syndication fees, and premiums over or discounts from face amounts of acquired loans. Excludes amounts 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) -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 840 -SubTopic 30 -Section 50 -Paragraph 4 -Subparagraph (a)(4) -URI http://asc.fasb.org/extlink&oid=84165051&loc=d3e45377-112738 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=118936363&loc=d3e5074-111524 Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 20 -Section 50 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=84159169&loc=d3e10152-111534 + Details
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