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Note 18 - Share-based Compensation (Details Textual) - USD ($) $ / shares in Units, $ in Millions | 12 Months Ended |  |  |  |
--- | --- | --- | --- | --- | ---
Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018 | Apr. 29, 2020 | Apr. 26, 2017 | Apr. 24, 2013 | Apr. 28, 2010
Share-based Payment Arrangement, Expense | $ 6.0 | $ 11.4 | $ 8.3 |  |  |  |
Excess Tax Benefit from Share-based Compensation, Operating Activities | $ 0.3 | $ 1.1 | $ 2.1 |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value (in dollars per share) | $ 18.45 | $ 15.37 | $ 16.07 |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period, Intrinsic Value | $ 3.3 | $ 6.8 | $ 10.3 |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Intrinsic Value | 8.4 |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Intrinsic Value | $ 7.5 |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Remaining Contractual Term (Year) | 5 years 8 months 12 days |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Weighted Average Remaining Contractual Term (Year) | 5 years |  |  |  |  |  |
Deferred Compensation Liability, Current and Noncurrent, Total | $ 0.3 | 0.2 |  |  |  |  |
Share-based Payment Arrangement, Option [Member] |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period (Year) | 3 years |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Expiration Period (Year) | 10 years |  |  |  |  |  |
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount, Total | $ 1.0 |  |  |  |  |  |
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition (Year) | 1 year 1 month 6 days |  |  |  |  |  |
Share-based Payment Arrangement, Option [Member] | Vesting Yearly [Member] |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage | 33.33% |  |  |  |  |  |
Restricted Stock [Member] |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period (Year) | 3 years |  |  |  |  |  |
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount, Total | $ 1.2 |  |  |  |  |  |
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition (Year) | 1 year 9 months 18 days |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period, Fair Value | $ 0.7 | $ 1.0 | $ 1.0 |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period (in shares) | 10,038 |  |  |  |  |  |
Performance Shares [Member] |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period (Year) | 3 years |  |  |  |  |  |
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount, Total | $ 0.9 |  |  |  |  |  |
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition (Year) | 1 year |  |  |  |  |  |
Share Based Compensation Arrangement by Share Based Payment Award, Percentage of Maximum Increase in Number of Shares Participant Receives Based on Achievement of Performance Goals | 200.00% |  |  |  |  |  |
Share Based Compensation Arrangement by Share Based Payment Award, Potential Lowest Number of Shares Participant Receives Based on Achievement of Performance Goals | 0.00% |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period (in shares) | 29,595 | 0 | 0 |  |  |  |
Restricted Stock Units (RSUs) [Member] |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period (Year) | 3 years |  |  |  |  |  |
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount, Total | $ 2.3 |  |  |  |  |  |
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition (Year) | 1 year 4 months 24 days |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period, Fair Value | $ 2.6 | $ 2.2 | $ 0.9 |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period (in shares) | 37,389 |  |  |  |  |  |
The 2010 Plan [Member] |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized (in shares) |  |  |  |  |  | 2,600,000 | 1,500,000
The 2017 Plan [Member] |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized (in shares) |  |  |  |  | 1,200,000 |  |
The 2020 Plan [Member] |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized (in shares) |  |  |  | 1,750,000 |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant (in shares) | 1,833,080 |  |  |  |  |  |
The 2010 Plan and the 2017 Plan [Member] |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant (in shares) | 1,081,982 |  |  |  |  |  |

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- Definition The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable. + 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 -URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901 + Details
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- Definition Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the 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 (a)(2) -URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901 + Details
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