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Note 4 - Investments (Details Textual) - USD ($) $ in Millions | Mar. 31, 2025 | Dec. 31, 2024
--- | --- | ---
Investment Owned, Fair Value | $ 1,096.6 | $ 862.3
European Smaller Companies Trust PLC [Member] |  |
Investment Owned, Fair Value | $ 52.0 |
Privacore [Member] |  |
Equity Method Investment, Ownership Percentage | 49.00% |
Long Tail Alpha Investment [Member] |  |
Equity Method Investment, Ownership Percentage | 20.00% |

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