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Note 8 - Loans and Related Allowance for Loan and Lease Losses (Details Textual) - USD ($) | 3 Months Ended | 12 Months Ended
--- | --- | ---
Mar. 31, 2018 | Mar. 31, 2017 | Dec. 31, 2017
Loans and Leases Receivable, Deferred Income, Total | $ 1,500,000 |  | $ 1.50
Financing Receivable, Modifications, Recorded Investment | 9,100,000 |  | $ 5,400,000
Number of Days Past Due |  |  | 90 days
Loans and Leases Receivable, Impaired, Interest Lost on Nonaccrual Loans | 369,000 |  | $ 437,000
Provision for Loan, Lease, and Other Losses, Total | $ 210,000 | $ 165,000 |
Financing Receivable, Modifications, Subsequent Default, Number of Contracts | 0 |  |
Commercial And Industrial [Member] |  |  |
Provision for Loan, Lease, and Other Losses, Total | $ 157,000 | 110,000 |
Commercial And Industrial [Member] | Special Mention [Member] |  |  |
Financing Receivable, Modifications, Recorded Investment | 5,800,000 |  |
Real Estate Construction Porfolio Segment [Member] |  |  |
Provision for Loan, Lease, and Other Losses, Total | $ (238,000) | $ (3,000) |
Loans and Leases Receivable, Historical Loss Rate | 0.775% | (0.127%) |
Residential Loan [Member] | Real Estate Mortgage Portfolio Segment [Member] |  |  |
Provision for Loan, Lease, and Other Losses, Total | $ 2,000 | $ (234,000) |
Financing Receivable, Modifications, Subsequent Default, Number of Contracts |  | 1 |
Financing Receivable, Modifications, Subsequent Default, Recorded Investment |  | $ 33,000 |
Threshold For Loans Evaluated For Impairment [Member] |  |  |
Loans and Leases Receivable, before Fees, Gross, Total | 1,000,000 |  |
Outside Consultant [Member] | Threshold For Loans Evaluated For Impairment [Member] |  |  |
Loans and Leases Receivable, before Fees, Gross, Total | 250,000 |  |
Criticized Relationships [Member] | Threshold For Loans Evaluated For Impairment [Member] |  |  |
Financing Receivable, Gross | $ 125,000 |  |

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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 The amount of the outstanding recorded investment related to financing receivables that have been modified by troubled debt restructurings. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 40 -Section 50 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=82895541&loc=d3e18845-111554 + Details
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- Definition Number of financing receivables that have been modified by troubled debt restructurings within the previous 12 months and for which there was a payment default. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 34 -URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953682-111524 + Details
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- Definition Amount of investment related to financing receivables modified by troubled debt restructurings within the previous 12 months, for which there was a payment default. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 34 -URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953682-111524 + 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=82891408&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=84173941&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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- Definition Reflects the amount of additional interest income that would have been recorded if impaired or nonperforming loans were instead current, in compliance with their original terms, and outstanding throughout the reporting period or since origination (if held for part of the period). + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 40 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=82895541&loc=d3e18794-111554 + Details
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- Definition Amount representing an agreement for an unconditional promise by the maker to pay the entity (holder) a definite sum of money at a future date. Such amount may include accrued interest receivable in accordance with the terms of the note. The note also may contain provisions and related items including a discount or premium, payable on demand, secured, or unsecured, interest bearing or noninterest bearing, among a myriad of other features and characteristics. Excludes amounts related to receivables held-for-sale. + 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 210.9-03.10(3)) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 + Details
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