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Note 9 - Fair Value (Details Textual) - USD ($) | 1 Months Ended | 3 Months Ended | 9 Months Ended |
--- | --- | --- | --- | ---
Jan. 25, 2022 | Sep. 30, 2023 | Sep. 30, 2022 | Sep. 30, 2023 | Sep. 30, 2022 | Mar. 31, 2022
Long-Term Debt |  | $ 27,537,830 |  | $ 27,537,830 |  |
Fair Value Adjustment of Warrants | $ (1,837,211) | $ (0) | $ (0) | $ (0) | $ (1,837,211) |
Sky Harbour Group Corporation Class A Common Stock [Member] |  |  |  |  |  |
Equity Method Investment, Ownership Percentage |  | 22.90% |  | 22.90% |  | 22.90%
Equity Method Investment, Shares (in shares) | 4,500,000 | 13,118,474 |  | 13,118,474 |  | 13,118,474
Equity Method Investment, Quoted Market Value |  | $ 58,900,000 |  | $ 58,900,000 |  |
Boston Omaha [Member] |  |  |  |  |  |
Equity Securities, FV-NI, Total |  | 84,000,000 |  | 84,000,000 |  |
The 24th Street Funds, Special Purpose Entities [Member] |  |  |  |  |  |
Investment Owned, Fair Value |  | 43,695,899 |  | 43,695,899 |  |
Private Placement Warrants [Member] |  |  |  |  |  |
Fair Value Adjustment of Warrants |  |  |  | 12,352 | $ 1,408,860 |
Fair Value, Inputs, Level 2 [Member] |  |  |  |  |  |
Long-Term Debt, Fair Value |  | $ 24,892,061 |  | $ 24,892,061 |  |

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