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Investment Securities - Unrealized Gain (Loss) on Investments (Details) - USD ($) $ in Thousands | 3 Months Ended
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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)

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- 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 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=123581744&loc=d3e27405-111563 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SX 210.5-03.7(c),9(a)) -URI http://asc.fasb.org/extlink&oid=123367319&loc=SL114868664-224227 Reference 3: http://www.xbrl.org/2003/role/recommendedDisclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=123570139&loc=d3e3602-108585 + Details
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