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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%

X

- Definition

The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

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Fair value of investment in security owned.

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