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Note 9 - Investments, Including Investments Accounted for Using the Equity Method (As Restated) (Details Textual) - USD ($) |  |  | 1 Months Ended | 3 Months Ended | 9 Months Ended | 12 Months Ended
--- | --- | --- | --- | --- | --- | ---
May 31, 2018 | Dec. 31, 2017 | May 31, 2019 | Jan. 31, 2018 | May 01, 2021 | Sep. 30, 2020 | Dec. 31, 2020 | Dec. 31, 2019
Gain (Loss) on Sale of Investments, Total |  |  |  |  |  |  | $ 5,714,207 | $ 572,181
Proceeds from Redemption of Preferred Units |  |  |  |  |  |  | 12,000,000 | 0
Payments to Acquire Equity Method Investments |  |  |  |  |  |  | 6,000,000 | 264,834
Dream Finders Holdings, LLC [Member] | Term Loan Receivable [Member] |  |  |  |  |  |  |  |
Notes Receivable, Related Parties |  |  |  |  |  |  | $ 20,000,000 |
Note Receivable, Interest Rate |  |  |  |  |  |  | 14.00% |
Dream Finders Holdings, LLC [Member] | Term Loan Receivable [Member] | Forecast [Member] |  |  |  |  |  |  |  |
Note Receivable, Monthly Payments |  |  |  |  | $ 5,000,000 |  |  |
Unconsolidated Affiliates [Member] |  |  |  |  |  |  |  |
Equity Method Investments |  |  |  |  |  |  | $ 687,707 |
Unconsolidated Affiliates [Member] | Minimum [Member] |  |  |  |  |  |  |  |
Equity Method Investment, Ownership Percentage |  |  |  |  |  |  | 5.60% |
Unconsolidated Affiliates [Member] | Maximum [Member] |  |  |  |  |  |  |  |
Equity Method Investment, Ownership Percentage |  |  |  |  |  |  | 30.00% |
The 24th Street Fund I, LLC [Member] |  |  |  |  |  |  |  |
Payments to Acquire Equity Method Investments |  |  |  |  |  |  | $ 6,000,000 |
Breezeway Homes Inc. [Member] |  |  |  |  |  |  |  |
Preferred Stock, Dividend Rate, Per-Dollar-Amount (in dollars per share) |  |  |  | $ 2,665 |  |  |  |
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 |  |  |  |  |  |  | 13,159 |
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% |  |  |  |  |  |  |
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 |  |
Equity Investments [Member] |  |  |  |  |  |  |  |
Other than Temporary Impairment Losses, Investments, Total |  |  |  |  |  |  | $ 0 | $ 0

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