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Note 9 - Fair Value (Details Textual) | 6 Months Ended |  |
--- | --- | --- | ---
Jun. 30, 2024 USD ($) shares | Jun. 30, 2023 USD ($) | Dec. 31, 2023 USD ($) | Jan. 25, 2022 shares
Long-Term Debt | $ 26,934,575 |  |  |
Boston Omaha [Member] |  |  |  |
Equity Securities, FV-NI, Total | 84,000,000 |  |  |
The 24th Street Funds, Special Purpose Entities [Member] |  |  |  |
Investment Owned, Fair Value | $ 56,000,000 |  | $ 65,000,000 |
The 24th Street Funds, Special Purpose Entities [Member] | Measurement Input, Cap Rate [Member] | Minimum [Member] |  |  |  |
Investment Company, Investment Owned, Measurement Input | 0.065 |  |  |
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 | 18.60% |  |  |
Equity Method Investment, Shares (in shares) | shares | 12,440,642 |  |  | 4,500,000
Equity Method Investment, Quoted Market Value | $ 115,100,000 |  |  |
Private Placement Warrants [Member] |  |  |  |
Fair Value Adjustment of Warrants | 4,000,000 | $ 900,000 |  |
Fair Value, Inputs, Level 2 [Member] |  |  |  |
Long-Term Debt, Fair Value | $ 24,667,212 |  |  |

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