Investments - Summary of Investments (Details) - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021
Summary of Investment Holdings [Line Items]
Investments owned	$ 243,483	$ 273,418
Long-term incentive compensation obligations	52,500	63,800
Seed capital
Summary of Investment Holdings [Line Items]
Investments owned	320,500	379,000
Equity securities | Long-term incentive compensation-related
Summary of Investment Holdings [Line Items]
Investments owned	24,128	32,237
Equity securities | Seed capital
Summary of Investment Holdings [Line Items]
Investments owned	127,383	133,992
Equity securities | Other
Summary of Investment Holdings [Line Items]
Investments owned	2,232	18,243
Exchange-traded options
Summary of Investment Holdings [Line Items]
Investments owned	445	1,893
Investments in limited partnership hedge funds | Long-term incentive compensation-related
Summary of Investment Holdings [Line Items]
Investments owned	28,333	31,602
Investments in limited partnership hedge funds | Seed capital
Summary of Investment Holdings [Line Items]
Investments owned	26,392	19,318
Time deposits
Summary of Investment Holdings [Line Items]
Investments owned	21,942	21,024
Other
Summary of Investment Holdings [Line Items]
Investments owned	$ 12,628	$ 15,109