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Note 16 - Income Taxes (Details Textual) - USD ($) $ in Thousands |  | 12 Months Ended
--- | --- | ---
Jan. 01, 2019 | Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017
Unrecognized Tax Benefits, Income Tax Penalties Accrued |  | $ 0 | $ 0 |  |
Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent |  | 21.00% | 21.00% | 21.00% | 35.00%
Tax Cuts and Jobs Act, Reclassification from AOCI to Retained Earnings, Tax Effect | $ 200 |  |  |  |
Domestic Tax Authority [Member] |  |  |  |  |
Tax Credit Carryforward, Amount |  | $ 2,000 |  |  |
Domestic Tax Authority [Member] | Capital Loss Carryforward [Member] |  |  |  |  |
Tax Credit Carryforward, Amount |  | $ 1,000 |  |  |
Tax Credit Carryforward, Expiration Year |  | 2024 |  |  |
Domestic Tax Authority [Member] | Minimum [Member] |  |  |  |  |
Tax Credit Carryforward, Expiration Year |  | 2023 |  |  |
Domestic Tax Authority [Member] | Maximum [Member] |  |  |  |  |
Tax Credit Carryforward, Expiration Year |  | 2034 |  |  |
State and Local Jurisdiction [Member] |  |  |  |  |
Tax Credit Carryforward, Amount |  | $ 4,200 |  |  |
Tax Credit Carryforward, Expiration Year |  | 2021 |  |  |
Operating Loss Carryforwards, Total |  | $ 30,000 |  |  |
State and Local Jurisdiction [Member] | Minimum [Member] |  |  |  |  |
Operating Loss Carryforwards, Expiration Year |  | 2021 |  |  |
State and Local Jurisdiction [Member] | Maximum [Member] |  |  |  |  |
Operating Loss Carryforwards, Expiration Year |  | 2038 |  |  |
Foreign Tax Authority [Member] |  |  |  |  |
Operating Loss Carryforwards, Total |  | $ 4,400 |  |  |
Foreign Tax Authority [Member] | Minimum [Member] |  |  |  |  |
Operating Loss Carryforwards, Expiration Year |  | 2023 |  |  |
Foreign Tax Authority [Member] | Maximum [Member] |  |  |  |  |
Operating Loss Carryforwards, Expiration Year |  | 2030 |  |  |

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- Definition Percentage of domestic federal statutory tax rate applicable to pretax income (loss). + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SAB Topic 6.I.Fact.4) -URI http://asc.fasb.org/extlink&oid=116825942&loc=d3e330036-122817 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 12 -URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32687-109319 + Details
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