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Investment Securities - Unrealized Gain (Loss) on Investments (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Marketable Securities [Line Items]
Unrealized Gain (Loss) on Investments	$ (3,928)	$ 19
Consolidated Entity Excluding Variable Interest Entities (VIE)
Investments, Debt and Equity Securities [Abstract]
Net investment gain (loss)	(4,752)	196
Marketable Securities [Line Items]
Net investment gain (loss)	(4,752)	196
Seed Investments
Investments, Debt and Equity Securities [Abstract]
Net investment gain (loss)	(1,638)	477
Marketable Securities [Line Items]
Net investment gain (loss)	(1,638)	477
Long-Term Cash Awards
Investments, Debt and Equity Securities [Abstract]
Net investment gain (loss)	(2,961)	(105)
Marketable Securities [Line Items]
Net investment gain (loss)	(2,961)	(105)
Other
Investments, Debt and Equity Securities [Abstract]
Net investment gain (loss)	(153)	(176)
Marketable Securities [Line Items]
Net investment gain (loss)	$ (153)	$ (176)

X

- Definition

Amount of realized and unrealized gain (loss) on investment.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
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Amount of unrealized gain (loss) on investment.

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