Note 19 - Fair Value of Financial Instruments - Fair Value Measurement Inputs and Valuation Techniques (Details) $ in Thousands	Sep. 30, 2021 USD ($) Rate	Dec. 31, 2020 USD ($) Rate
Real estate investments, fair value	$ 10,662	$ 10,662
Limited Liability Investments [Member]
Limited liability investments, at fair value	18,180	32,811
Valuation, Market Approach [Member] | Fair Value, Inputs, Level 3 [Member] | Valuation Multiples [Member]
Stock-based compensation liabilities	$ 1,306	$ 443
Stock-based compensation liabilities (Rate) | Rate	6.0	6.0
Valuation, Market Approach [Member] | Fair Value, Inputs, Level 3 [Member] | Valuation Multiples [Member] | Limited Liability Investments [Member]
Limited liability investments, at fair value	$ 3,744	$ 3,263
Valuation, Market Approach [Member] | Fair Value, Inputs, Level 3 [Member] | Valuation Multiples [Member] | Limited Liability Investments [Member] | Minimum [Member]
Limited liability investments, at fair value (Rate) | Rate	3.1	3.1
Valuation, Market Approach [Member] | Fair Value, Inputs, Level 3 [Member] | Valuation Multiples [Member] | Limited Liability Investments [Member] | Maximum [Member]
Limited liability investments, at fair value (Rate) | Rate	8.0	8.0
Valuation, Market and Income Approach [Member] | Fair Value, Inputs, Level 3 [Member] | Measurement Input, Cap Rate [Member]
Real estate investments, fair value	$ 10,662	$ 10,662
Real estate investments (Rate)	7.5	7.5