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Investment Securities - Unrealized Gain (Loss) on Investments (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
Investments, Debt and Equity Securities [Abstract]
Unrealized gain (loss) on investment securities held at the end of the period	$ 7,891	$ (3,928)
Consolidated Entity Excluding Variable Interest Entities (VIE)
Marketable Securities [Line Items]
Other net investment gain (loss)	9,257	(4,752)
Seed Investments
Marketable Securities [Line Items]
Other net investment gain (loss)	1,710	(1,638)
Long-Term Cash Awards
Marketable Securities [Line Items]
Other net investment gain (loss)	7,018	(2,961)
Other
Marketable Securities [Line Items]
Other net investment gain (loss)	$ 529	$ (153)

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
-Paragraph 10
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Amount of unrealized gain (loss) on investment.

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