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Investment Securities - Unrealized Gain (Loss) on Investments (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Investments, Debt and Equity Securities [Abstract]
Unrealized gain (loss) on investment securities held at the end of the period	$ 3,299	$ (13,542)	$ 10,359	$ (17,470)
Consolidated Entity Excluding Variable Interest Entities (VIE)
Marketable Securities [Line Items]
Other net investment gain (loss)	4,224	(13,414)	13,481	(18,166)
Seed Investments
Marketable Securities [Line Items]
Other net investment gain (loss)	(500)	(1,298)	1,210	(2,936)
Long-Term Cash Awards
Marketable Securities [Line Items]
Other net investment gain (loss)		(12,244)		(15,205)
Other
Marketable Securities [Line Items]
Other net investment gain (loss)	$ 1,161	$ 128	$ 1,690	$ (25)

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
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Amount of unrealized gain (loss) on investment.

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