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Investment Securities - Unrealized Gain (Loss) on Investments (Details) - USD ($) $ in Thousands | 3 Months Ended | 6 Months Ended
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Jun. 30, 2022 | Jun. 30, 2021 | Jun. 30, 2022 | Jun. 30, 2021
Investments, Debt and Equity Securities [Abstract] |  |  |  |
Unrealized gain (loss) on investment securities held at the end of the period | $ (13,542) | $ 3,988 | $ (17,470) | $ 4,007
Consolidated Entity Excluding Variable Interest Entities (VIE) |  |  |  |
Marketable Securities [Line Items] |  |  |  |
Net investment gain (loss) | (13,414) | 3,934 | (18,166) | 4,131
Seed Investments |  |  |  |
Marketable Securities [Line Items] |  |  |  |
Net investment gain (loss) | (1,298) | 1,378 | (2,936) | 1,855
Long-Term Cash Awards |  |  |  |
Marketable Securities [Line Items] |  |  |  |
Net investment gain (loss) | (12,244) | 2,578 | (15,205) | 2,473
Other |  |  |  |
Marketable Securities [Line Items] |  |  |  |
Net investment gain (loss) | $ 128 | $ (22) | $ (25) | $ (197)

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