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Investment Securities - Unrealized Gain (Loss) on Investments (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Investments, Debt and Equity Securities [Abstract]
Unrealized gain (loss) on investment securities held at the end of the period	$ (3,901)	$ (6,675)	$ 6,458	$ (24,145)
Consolidated Entity Excluding Variable Interest Entities (VIE)
Marketable Securities [Line Items]
Other net investment gain (loss)	(2,152)	(5,563)	11,329	(23,729)
Seed Investments
Marketable Securities [Line Items]
Other net investment gain (loss)	214	(1,649)	1,424	(4,585)
Long-Term Cash Awards
Marketable Securities [Line Items]
Other net investment gain (loss)		(3,987)		(19,192)
Other
Marketable Securities [Line Items]
Other net investment gain (loss)	$ 2,088	$ 73	$ 3,778	$ 48

X

- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/recommendedDisclosureRef
-Topic 230
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 28
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482740/230-10-45-28

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 220
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.7(c),9(a))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483621/220-10-S99-2

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+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-Section 45
-Paragraph 28
-Subparagraph (b)
-SubTopic 10
-Topic 230
-Publisher FASB
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