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Investment Securities - Schedule of available-for-sale securities (Details) - USD ($) $ in Thousands | 12 Months Ended
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Dec. 31, 2022 | Dec. 31, 2021 | Dec. 31, 2020
Gain (Loss) on Securities [Line Items] |  |  |
Unrealized gain (loss) on investment securities held at the end of the period | $ (14,799) | $ 1,602 | $ 716
Investment securities | 85,415 | 47,878 |
Seed Investments |  |  |
Gain (Loss) on Securities [Line Items] |  |  |
Net investment gain (loss) of consolidated investment products | (3,407) | (401) | 160
Long-Term Cash Awards |  |  |
Gain (Loss) on Securities [Line Items] |  |  |
Net investment gain (loss) of consolidated investment products | (13,198) | 2,716 | 0
Other Investments |  |  |
Gain (Loss) on Securities [Line Items] |  |  |
Net investment gain (loss) of consolidated investment products | 332 | (559) | 145
Consolidated Entity Excluding Variable Interest Entities (VIE) |  |  |
Gain (Loss) on Securities [Line Items] |  |  |
Net investment gain (loss) of consolidated investment products | (16,273) | $ 1,756 | $ 305
Long-Term Cash Awards |  |  |
Gain (Loss) on Securities [Line Items] |  |  |
Investment securities | $ 63,300 |  |

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