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Note 6 - Share-based Payments (Details Textual) $ in Millions | 9 Months Ended
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Sep. 30, 2020 USD ($) shares
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount, Total | $ | $ 3.9
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition (Year) | 1 year 10 months 24 days
Stock Performance Awards [Member] | Executive Officer [Member] | The 2014 Stock Incentive Plan [Member] |
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized (in shares) | 55,000
Period Specified for Average Adjusted Return (Year) | 3 years
Number of Trading Days (Day) | 20 days
Number of Shares Authorized for Actual Payment (in shares) | 82,500
Stock Performance Awards [Member] | Executive Officer [Member] | The 2014 Stock Incentive Plan [Member] | Minimum [Member] |
Percentage of Target Amount as Actual Payment | 0.00%
Stock Performance Awards [Member] | Executive Officer [Member] | The 2014 Stock Incentive Plan [Member] | Maximum [Member] |
Percentage of Target Amount as Actual Payment | 150.00%
Stock Performance Awards [Member] | Executive Officer [Member] | The 2014 Stock Incentive Plan [Member] | Share-based Payment Arrangement, Tranche One [Member] |
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized (in shares) | 27,500
Stock Performance Awards [Member] | Executive Officer [Member] | The 2014 Stock Incentive Plan [Member] | Share-based Payment Arrangement, Tranche Two [Member] |
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized (in shares) | 27,500

X
- Definition Represents the number of shares authorized for actual payment. + References No definition available. + Details
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Data Type: | xbrli:sharesItemType
Balance Type: | na
Period Type: | instant

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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X
- Definition Represents the percentage of target amount as a actual payment. + References No definition available. + Details
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X
- Definition Represents the period specified for average adjusted return, used to determine the achievement of a target. + References No definition available. + Details
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- Definition Amount of cost not yet recognized for nonvested award 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 (i) -URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901 + Details
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X
- Definition Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. + 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 (i) -URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901 + 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=120381028&loc=d3e5070-113901 + Details
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- Details
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