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Note 7 - Income Taxes (Details Textual) - USD ($) $ in Millions | 12 Months Ended
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Dec. 31, 2023 | Dec. 31, 2022
Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent |  | 21.00%
Effective Income Tax Rate Reconciliation, Percent, Total | 9.00% | 9.00%
Domestic Tax Authority [Member] | Pre-2018 [Member] |  |
Operating Loss Carryforwards | $ 13.4 |
Domestic Tax Authority [Member] | Post 2017 [Member] |  |
Operating Loss Carryforwards | $ 60.7 |

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- Definition Percentage of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 740 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 12 -Publisher FASB -URI https://asc.fasb.org//1943274/2147482685/740-10-50-12 + Details
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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 -Topic 235 -SubTopic 10 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.4-08(h)(2)) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480678/235-10-S99-1 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 740 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 12 -Publisher FASB -URI https://asc.fasb.org//1943274/2147482685/740-10-50-12 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Topic 740 -SubTopic 10 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SAB Topic 6.I.Fact.4) -Publisher FASB -URI https://asc.fasb.org//1943274/2147479360/740-10-S99-1 + Details
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