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Note I - Income Taxes (Details Textual) - USD ($) $ in Thousands | 3 Months Ended | 9 Months Ended | 12 Months Ended
--- | --- | --- | ---
Sep. 30, 2021 | Sep. 30, 2020 | Sep. 30, 2021 | Sep. 30, 2020 | Dec. 31, 2020
Income Tax Expense (Benefit), Total | $ 172 | $ (53) | $ 1,018 | $ (12,863) |
Effective Income Tax Rate Reconciliation, Percent, Total | 3.80% | 3.20% | 7.20% | 82.40% |
Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent | 21.00% | 21.00% | 21.00% | 21.00% |
Expected Proceeds from Income Tax Refunds, Carryback of Loss |  |  | $ 7,600 |  |
State and Local Jurisdiction [Member] |  |  |  |  |
Open Tax Year |  |  | 2014 2015 2016 2017 2018 2019 2020 |  |
Foreign Tax Authority [Member] |  |  |  |  |
Open Tax Year |  |  | 2016 2017 2018 2019 2020 |  |
Tax Year 2019 [Member] |  |  |  |  |
Proceeds from Income Tax Refunds |  |  |  |  | $ 6,400
Tax Year 2018 [Member] |  |  |  |  |
Proceeds from Income Tax Refunds |  |  |  |  | $ 3,200

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