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Note 8 - Investments, Including Investments Accounted for Using the Equity Method (Details Textual) - USD ($) |  |  |  |  |  | 1 Months Ended | 9 Months Ended | 12 Months Ended |
--- | --- | --- | --- | --- | --- | --- | --- | --- | ---
Sep. 14, 2021 | Jan. 25, 2021 | Jan. 20, 2021 | May 31, 2018 | Dec. 31, 2017 | May 31, 2019 | Jan. 31, 2018 | Sep. 30, 2021 | Sep. 30, 2020 | Dec. 31, 2020 | Oct. 02, 2020
Proceeds from Redemption of Preferred Units |  |  |  |  |  |  |  | $ 0 | $ 12,000,000 |  |
Payments to Acquire Equity Method Investments |  |  |  |  |  |  |  | $ (0) | 3,175,000 |  |
Dream Finders Holdings, LLC [Member] | Term Loan Receivable [Member] |  |  |  |  |  |  |  |  |  |  |
Notes Receivable, Related Parties |  |  |  |  |  |  |  |  |  |  | $ 20,000,000
Note Receivable, Interest Rate |  |  |  |  |  |  |  |  |  |  | 14.00%
Dream Finders Homes, Inc. [Member] |  |  |  |  |  |  |  |  |  |  |
Proceeds from Collection of Notes Receivable |  | $ 20,567,776 |  |  |  |  |  |  |  |  |
Business Combination Agreement with SHG [Member] |  |  |  |  |  |  |  |  |  |  |
Payments to Acquire Businesses, Gross | $ 55,000,000 |  |  |  |  |  |  |  |  |  |
Common Class A [Member] | Business Combination Agreement with SHG [Member] |  |  |  |  |  |  |  |  |  |  |
Business Acquisition, Additional Financing in Support of Transaction, Number of Shares into which the Additional Equity Investment Will Be Converted (in shares) | 5,500,000 |  |  |  |  |  |  |  |  |  |
Business Acquisition, Additional Financing in Support of Transaction, Shares into which the Additional Equity Investment Will Be Converted, Price Per Share (in dollars per share) | $ 10 |  |  |  |  |  |  |  |  |  |
Common Class A [Member] | IPO [Member] | Dream Finders Homes, Inc. [Member] |  |  |  |  |  |  |  |  |  |  |
Stock Issued During Period, Shares, New Issues (in shares) |  |  | 9,600,000 |  |  |  |  |  |  |  |
Shares Issued, Price Per Share (in dollars per share) |  |  | $ 13.00 |  |  |  |  |  |  |  |
Unconsolidated Affiliates [Member] | Minimum [Member] |  |  |  |  |  |  |  |  |  |  |
Equity Method Investment, Ownership Percentage |  |  |  |  |  |  |  | 5.60% |  |  |
Unconsolidated Affiliates [Member] | Maximum [Member] |  |  |  |  |  |  |  |  |  |  |
Equity Method Investment, Ownership Percentage |  |  |  |  |  |  |  | 49.90% |  |  |
Logic Real Estate Companies and 24th Street Holding Company [Member] |  |  |  |  |  |  |  |  |  |  |
Equity Method Investments |  |  |  |  |  |  |  | $ 781,970 |  |  |
The 24th Street Fund I, LLC [Member] |  |  |  |  |  |  |  |  |  |  |
Equity Method Investment, Ownership Percentage |  |  |  |  |  |  |  | 49.90% |  |  |
Payments to Acquire Equity Method Investments |  |  |  |  |  |  |  |  |  | $ 6,000,000 |
Breezeway Homes Inc. [Member] |  |  |  |  |  |  |  |  |  |  |
Preferred Stock, Dividend Rate, Per-Dollar-Amount (in dollars per share) |  |  |  |  |  |  | $ 0.2665 |  |  |  |
Preferred Stock [Member] | Breezeway Homes Inc. [Member] |  |  |  |  |  |  |  |  |  |  |
Debt Conversion, Converted Instrument, Shares Issued (in shares) |  |  |  |  |  |  | 31,227 |  |  |  |
US Treasury Notes Securities [Member] |  |  |  |  |  |  |  |  |  |  |
Gain (Loss) on Sale of Investments, Total |  |  |  |  |  |  |  | $ (63,994) | $ 7,318 |  |
Voting Common Stock of Privately Held Company CB&T Holding Corporation [Member] |  |  |  |  |  |  |  |  |  |  |
Payments to Acquire Long-term Investments |  |  |  | $ 19,058,485 |  |  |  |  |  |  |
Cost Method Investment, Ownership Percentage |  |  |  | 14.99% |  |  |  |  |  |  |
Equity Investments [Member] |  |  |  |  |  |  |  |  |  |  |
Other than Temporary Impairment Losses, Investments, Total |  |  |  |  |  |  |  | $ 0 |  |  |
Non-voting Common Units of Dream Finders Holdings, LLC [Member] |  |  |  |  |  |  |  |  |  |  |
Payments to Acquire Long-term Investments |  |  |  |  | $ 10,000,000 |  |  |  |  |  |
Cost Method Investment, Ownership Percentage |  |  |  |  | 5.60% |  |  |  |  |  |
Non-voting Preferred Units of DFH LLC [Member] |  |  |  |  |  |  |  |  |  |  |
Payments to Acquire Long-term Investments |  |  |  |  |  | $ 12,000,000 |  |  |  |  |
Mandatory Preferred Return, Percent |  |  |  |  |  | 14.00% |  |  |  |  |
Percent of Preferred Units Convertible to Non-voting Common Units |  |  |  |  |  | 25.00% |  |  |  |  |
Proceeds from Redemption of Preferred Units |  |  |  |  |  |  |  |  |  | $ 12,000,000 |
DFH Class A Common Stock [Member] |  |  |  |  |  |  |  |  |  |  |
Equity Securities, FV-NI, Shares, Acquired from Conversion (in shares) |  |  | 4,681,099 |  |  |  |  |  |  |  |
Equity Securities, FV-NI, Shares, Purchase (in shares) |  |  | 120,000 |  |  |  |  |  |  |  |
Equity Securities, FV-NI, Shares, Purchase, Price Per Share (in dollars per share) |  |  | $ 13.00 |  |  |  |  |  |  |  |

X
- Definition With regard to the additional financing agreed to provide in support of the transaction, which will be funded prior to the closing of the business combination (if certain conditions are met), this element represents the number of shares into which the additional equity investment will be converted. + References No definition available. + Details
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- Definition With regard to the additional financing agreed to provide in support of the transaction, which will be funded prior to the closing of the business combination (if certain conditions are met), this element represents the price per share of the shares into which the additional equity investment will be converted. + References No definition available. + Details
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