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Note 18 - Subsequent Events (Details Textual) - USD ($) | 1 Months Ended | 3 Months Ended
--- | --- | ---
May 14, 2025 | Apr. 30, 2025 | Mar. 31, 2025 | Mar. 31, 2024
Proceeds from Long-Term Lines of Credit |  |  | $ 3,500,000 | $ 0
Subsequent Event [Member] | First National Bank of Omaha [Member] | Credit Facility [Member] | Boston Omaha Broadband Credit Facility [Member] |  |  |  |
Proceeds from Long-Term Lines of Credit |  | $ 4,000,000 |  |
Sky Harbour Group Corporation [Member] | Subsequent Event [Member] |  |  |  |
Investment Owned, Shares Sold (in shares) | 335,656 |  |  |
Proceeds from Sale of Investments | $ 3,800,000 |  |  |

X
- Definition The number of shares sold of investment. + References No definition available. + Details
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Balance Type: | na
Period Type: | duration

X
- Definition The cash inflow from sale of investments. + References No definition available. + Details
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Data Type: | xbrli:monetaryItemType
Balance Type: | debit
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X
- Definition The cash inflow from a contractual arrangement with the lender, including letter of credit, standby letter of credit and revolving credit arrangements, under which borrowings can be made up to a specific amount at any point in time with maturities due beyond one year or the operating cycle, if longer. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 14 -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482740/230-10-45-14 + Details
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- Details
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- Details
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X
- Details
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X
- Details
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Period Type: |

X
- Details
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Namespace Prefix: |
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Balance Type: |
Period Type: |