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Note 3 - Allowance for Loan Losses, Nonperforming Assets and Impaired Loans (Details Textual) $ in Thousands | 3 Months Ended | 12 Months Ended
--- | --- | ---
Mar. 31, 2018 USD ($) | Mar. 31, 2017 USD ($) | Dec. 31, 2017 USD ($)
Threshold for Designation to Impaired Status | $ 250 |  |
Interest and Fee Income, Loans and Leases, Total | 7,532 | $ 7,453 |
Financing Receivable, Reclassification to Held-for-sale | 0 |  |
Financing Receivable, Modifications, Recorded Investment | $ 10,648 | $ 8,387 | $ 7,897
Financing Receivable, Modifications, Number of Contracts | 2 | 0 |
Allowance for Credit Losses, Change in Method of Calculating Impairment | $ 0 |  |
Financing Receivable, Modifications, Subsequent Default, Number of Contracts | 0 | 0 |
Commercial Non Real Estate Segment [Member] | Commercial and Industrial [Member] |  |  |
Financing Receivable, Modifications, Number of Contracts | 2 |  |
Special Mention [Member] |  |  |
Increase in Percentage of Allocation Loans Rated Special Mention | 50.00% |  |
Classified Excluding Impaired [Member] |  |  |
Increase in Percentage of Allocation Loans Rated Classified | 100.00% |  |
Nonperforming Financial Instruments [Member] |  |  |
Interest and Fee Income, Loans and Leases, Total | $ 0 | $ 0 | $ 0

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- Definition Number of 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 10 -Section 50 -Paragraph 33 -URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953676-111524 + 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 The aggregate interest and fee income generated by: (1) loans the Entity has positive intent and ability to hold for the foreseeable future, or until maturity or payoff, including commercial and consumer loans, whether domestic or foreign, which may consist of: (a) industrial and agricultural; (b) real estate; and (c) real estate construction loans; (d) trade financing; (e) lease financing; (f) home equity lines-of-credit; (g) automobile and other vehicle loans; and (h) credit card and other revolving-type loans and (2) loans and leases held-for-sale which may include mortgage loans, direct financing, and sales-type leases. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 220 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-04.1) -URI http://asc.fasb.org/extlink&oid=114873765&loc=SL114874048-224260 + Details
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