Note 8 - Federal Income Tax (Details Textual) - USD ($) $ in Millions |
Dec. 31, 2025 |
Dec. 31, 2024 |
|---|---|---|
| Federal Excise Tax, Percent | 4.00% | |
| Operating Loss Carryforwards | $ 27.6 | $ 38.4 |
| Sales and Excise Tax Payable | 1.1 | 1.5 |
| Investment, Tax Basis, Cost | 705.3 | 766.8 |
| Investment, Tax Basis, Unrealized Gain | 26.6 | 14.8 |
| Investment, Tax Basis, Unrealized Loss | $ 84.6 | $ 83.7 |
| X | ||||||||||
- Definition The federal excise tax percent. No definition available.
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| X | ||||||||||
- Definition Amount of operating loss carryforward, before tax effects, available to reduce future taxable income under enacted tax laws. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Carrying value as of the balance sheet date of liabilities incurred through that date and payable for statutory sales and use taxes, including value added tax. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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| X | ||||||||||
- Definition Amount of cost of investment for federal income tax purpose. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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| X | ||||||||||
- Definition Amount of cumulative increase in investment from unrealized gain when value exceeds cost for federal income tax purpose. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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| X | ||||||||||
- Definition Amount of cumulative decrease in investment from unrealized loss when cost for federal income tax purpose exceeds value. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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