Note 19 - Fair Value of Financial Instruments - Fair Value Measurement Inputs and Valuation Techniques (Details) $ in Thousands	Jun. 30, 2022 USD ($)	Dec. 31, 2021 USD ($)
Limited liability investments, at fair value	$ 15,573	$ 14,804
Real estate investments, at fair value	10,662	10,662
Limited Liability Investments [Member]
Limited liability investments, at fair value	18,986	18,826
Valuation, Market Approach [Member] \| Fair Value, Inputs, Level 3 [Member]
Stock-based compensation liabilities, at fair value	$ 1,475	$ 1,402
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	$ 3,413	$ 4,022
Valuation Multiples [Member] \| Fair Value, Inputs, Level 3 [Member] \| Measurement Input, Cap Rate [Member] \| Minimum [Member]
Limited liability investments, measurement input	1.0	8.0
Valuation Multiples [Member] \| Fair Value, Inputs, Level 3 [Member] \| Measurement Input, Cap Rate [Member] \| Maximum [Member]
Limited liability investments, measurement input	9.0	1.0
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	7.5
Valuation, Income Approach [Member] \| Fair Value, Inputs, Level 3 [Member]
Contingent consideration, at fair value	$ 3,959	$ 2,458
Valuation, Income Approach [Member] \| Fair Value, Inputs, Level 3 [Member] \| Measurement Input, Discount Rate [Member]
Contingent consideration, measurement input	5.50	4.0
Valuation, Income Approach [Member] \| Fair Value, Inputs, Level 3 [Member] \| Measurement Input, Risk Free Interest Rate [Member]
Contingent consideration, measurement input	2.92	0.49
Valuation, Income Approach [Member] \| Fair Value, Inputs, Level 3 [Member] \| Measurement Input, Price Volatility [Member]
Contingent consideration, measurement input	16.0	15.0

Fair value of contingent consideration lability.

No definition available.

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- Definition

Value of input used to measure equity method investments.

+ References

No definition available.

+ Details

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- Definition

Represents fair value disclosure of real estate investments.

+ References

No definition available.

+ Details

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- Definition

Value of input used to measure real estate investments.

+ References

No definition available.

+ Details

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- Definition

Fair value of share-based compensation liability.

+ References

No definition available.

+ Details

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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 https://asc.fasb.org/extlink&oid=126976982&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 https://asc.fasb.org/extlink&oid=126960272&loc=d3e32014-111567

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