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Note 16 - Subsequent Events (Details Textual) - The 2014 Stock Incentive Plan [Member] - USD ($) $ in Millions |  |  | 12 Months Ended
--- | --- | --- | ---
Feb. 12, 2020 | Feb. 13, 2019 | Dec. 31, 2019
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized |  |  | 1,900,000
Executive Officer [Member] | Stock Performance Awards [Member] |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized |  | 55,600 |
Period Specified for Average Adjusted Return |  |  | 3 years
Number of Trading Days |  | 20 days |
Number of Shares Authorized for Actual Payment |  | 83,400 |
Executive Officer [Member] | Stock Performance Awards [Member] | Share-based Payment Arrangement, Tranche Two [Member] |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized |  | 27,800 |
Subsequent Event [Member] | Stock Performance Awards [Member] |  |  |
Period Specified for Average Adjusted Return | 3 years |  |
Number of Trading Days | 20 days |  |
Subsequent Event [Member] | Executive Officer [Member] | Stock Performance Awards [Member] |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Grant Date Fair Value | $ 3.3 |  |
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized | 55,000 |  |
Number of Shares Authorized for Actual Payment | 82,500 |  |
Subsequent Event [Member] | Executive Officer [Member] | Stock Performance Awards [Member] | Minimum [Member] |  |  |
Actual Payment, Percentage of Target Amount | 0.00% |  |
Subsequent Event [Member] | Executive Officer [Member] | Stock Performance Awards [Member] | Maximum [Member] |  |  |
Actual Payment, Percentage of Target Amount | 150.00% |  |
Subsequent Event [Member] | Executive Officer [Member] | Stock Performance Awards [Member] | Share-based Payment Arrangement, Tranche One [Member] |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized | 27,500 |  |
Subsequent Event [Member] | Executive Officer [Member] | Stock Performance Awards [Member] | Share-based Payment Arrangement, Tranche Two [Member] |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized | 27,500 |  |

X
- Definition Represents the actual payment as a percentage of the target amount. + References No definition available. + Details
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X
- Definition Represents the number of trading days used to set the average beginning and ending share prices for the change in total shareholder value over the performance measurement period and to establish the grant-date fair value of the performance share awards. + References No definition available. + Details
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- Definition The aggregate grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology. + References No definition available. + Details
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- Definition Number of shares authorized for issuance under share-based payment arrangement. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (a)(3) -URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901 + Details
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