Note 23 - Fair Value of Financial Instruments - Fair Value Measurement Inputs and Valuation Techniques (Details) $ in Thousands	Dec. 31, 2021 USD ($)	Dec. 31, 2020 USD ($)
Limited liability investments, at fair value	$ 14,804	$ 29,548
Real estate investments, at fair value	10,662	10,662
Limited Liability Investments [Member]
Limited liability investments, at fair value	18,826	32,811
Valuation, Market Approach [Member] \| Fair Value, Inputs, Level 3 [Member]
Stock-based compensation liabilities, at fair value	$ 1,402	$ 443
Valuation, Market Approach [Member] \| Fair Value, Inputs, Level 3 [Member] \| Valuation Multiples [Member]
Stock-based compensation liabilities, measurement input	6.0	6.0
Valuation, Market Approach [Member] \| Fair Value, Inputs, Level 3 [Member] \| Limited Liability Investments [Member]
Limited liability investments, at fair value	$ 4,022	$ 3,263
Valuation, Market Approach [Member] \| Fair Value, Inputs, Level 3 [Member] \| Limited Liability Investments [Member] \| Valuation Multiples [Member] \| Minimum [Member]
Limited liability investments, measurement input		3.1
Valuation, Market Approach [Member] \| Fair Value, Inputs, Level 3 [Member] \| Limited Liability Investments [Member] \| Valuation Multiples [Member] \| Maximum [Member]
Limited liability investments, measurement input		8.0
Valuation Multiples [Member] \| Fair Value, Inputs, Level 3 [Member] \| Measurement Input, Cap Rate [Member] \| Minimum [Member]
Limited liability investments, measurement input	1.0
Valuation Multiples [Member] \| Fair Value, Inputs, Level 3 [Member] \| Measurement Input, Cap Rate [Member] \| Maximum [Member]
Limited liability investments, measurement input	8.0
Valuation, Market and Income Approach [Member] \| Fair Value, Inputs, Level 3 [Member]
Real estate investments, at fair value	$ 10,662	$ 10,662
Valuation, Market and Income Approach [Member] \| Fair Value, Inputs, Level 3 [Member] \| Measurement Input, Cap Rate [Member]
Real estate investments, measurement input	7.5	0.075
Valuation, Income Approach [Member] \| Fair Value, Inputs, Level 3 [Member]
Contingent consideration, at fair value	$ 2,458
Valuation, Income Approach [Member] \| Fair Value, Inputs, Level 3 [Member] \| Measurement Input, Discount Rate [Member]
Contingent consideration, measurement input	4.0
Valuation, Income Approach [Member] \| Fair Value, Inputs, Level 3 [Member] \| Measurement Input, Risk Free Interest Rate [Member]
Contingent consideration, measurement input	0.49
Valuation, Income Approach [Member] \| Fair Value, Inputs, Level 3 [Member] \| Measurement Input, Price Volatility [Member]
Contingent consideration, measurement input	15.0

Fair value of contingent consideration lability.

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- Definition

Value of input used to measure equity method investments.

+ References

No definition available.

+ Details

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- Definition

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+ References

No definition available.

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- Definition

Value of input used to measure real estate investments.

+ References

No definition available.

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- Definition

Fair value of share-based compensation liability.

+ References

No definition available.

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- Definition

Value of input used to measure stock-based compensation liability.

+ References

No definition available.

+ Details

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- Definition

Value of input used to measure contingent consideration liability from business combination.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (bbb)(2)
-URI http://asc.fasb.org/extlink&oid=123874694&loc=d3e19207-110258

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- Definition

Fair value portion of investments accounted under the equity method.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 323
-SubTopic 10
-Section 25
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=125513658&loc=d3e32014-111567

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