Note 9 - Fair Value (Details Textual) - USD ($)	1 Months Ended	3 Months Ended
Jan. 25, 2022	Mar. 31, 2023	Mar. 31, 2022
Long-Term Debt		$ 28,114,900
Fair Value Adjustment of Warrants	$ (1,837,211)	$ (0)	$ (1,837,211)
Sky Harbour Group Corporation Class A Common Stock [Member]
Equity Method Investment, Ownership Percentage		22.95%	22.95%
Equity Method Investment, Shares (in shares)	4,500,000	13,118,474	13,118,474
Equity Method Investment, Quoted Market Value		$ 94,300,000
Boston Omaha [Member]
Equity Securities, FV-NI, Total		84,000,000
Private Placement Warrants [Member]
Fair Value Adjustment of Warrants		2,251,088	$ 7,410,988
Fair Value, Inputs, Level 2 [Member]
Long-Term Debt, Fair Value		$ 25,982,426

The number of shares.

No definition available.

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- 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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This item represents the aggregate value of each identified investment accounted for under the equity method of accounting based on the quoted market price for those investments in common stock for which a quoted market price is available.

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Amount of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

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Amount of expense (income) related to adjustment to fair value of warrant liability.

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Amount, after deduction of unamortized premium (discount) and debt issuance cost, of long-term debt. Excludes lease obligation.

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The fair value amount of long-term debt whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission.

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