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v3.25.1

Note 9 - Fair Value (Details Textual) | 3 Months Ended |  |
--- | --- | --- | ---
Mar. 31, 2025 USD ($) shares | Mar. 31, 2024 USD ($) | Dec. 31, 2024 USD ($) | Jan. 25, 2022 shares
Long-Term Debt | $ 26,309,906 |  |  |
Boston Omaha [Member] |  |  |  |
Equity Securities, FV-NI | 84,000,000 |  |  |
The 24th Street Funds, Special Purpose Entities [Member] |  |  |  |
Investment Owned, Fair Value | $ 42,200,000 |  | $ 46,900,000 |
The 24th Street Funds, Special Purpose Entities [Member] | Measurement Input, Cap Rate [Member] | Minimum [Member] |  |  |  |
Investment Company, Investment Owned, Measurement Input | 6.25 |  |  |
The 24th Street Funds, Special Purpose Entities [Member] | Measurement Input, Cap Rate [Member] | Maximum [Member] |  |  |  |
Investment Company, Investment Owned, Measurement Input | 0.0675 |  |  |
Sky Harbour Group Corporation Class A Common Stock [Member] |  |  |  |
Equity Method Investment, Ownership Percentage | 16.10% |  |  |
Equity Method Investment, Shares (in shares) | shares | 12,180,700 |  |  | 4,500,000
Equity Method Investment, Quoted Market Value | $ 158,500,000 |  |  |
Private Placement Warrants [Member] |  |  |  |
Fair Value Adjustment of Warrants | 1,235,165 | $ 8,000,000 |  |
Fair Value, Inputs, Level 2 [Member] |  |  |  |
Long-Term Debt, Fair Value | $ 24,431,161 |  |  |

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