Investments of Operating Entities and Consolidated Funds - Other Investments (Details) - USD ($) $ in Thousands	Dec. 31, 2019		Dec. 31, 2018
Investment Holdings [Line Items]
Other investments	$ 185,722		$ 181,407
Portfolio Funds, Consolidated Funds	175,769		186,395
Portfolio Funds
Investment Holdings [Line Items]
Other investments	114,504	[1]	124,741	[2]
Carried interest [Member]
Investment Holdings [Line Items]
Other investments	30,360	[1]	17,995	[2]
Equity Method Investments
Investment Holdings [Line Items]
Other investments	40,858		38,671
Enterprise LP [Member]
Investment Holdings [Line Items]
Portfolio Funds, Consolidated Funds	99,153		97,656
Merger Fund [Member]
Investment Holdings [Line Items]
Portfolio Funds, Consolidated Funds	$ 76,616		$ 88,739

[1] In accordance with US GAAP, certain investments are measured at fair value using the net asset value per share (or its equivalent) as a practical expedient. Carried interest in portfolio funds have not been classified in the fair value hierarchy. The fair value amounts presented in this table are intended to permit reconciliation of the fair value hierarchy to the amounts presented in the consolidated statement of financial condition.

[2] In accordance with US GAAP, certain investments are measured at fair value using the net asset value per share (or its equivalent) as a practical expedient. Carried interest in portfolio funds have not been classified in the fair value hierarchy. The fair value amounts presented in this table are intended to permit reconciliation of the fair value hierarchy to the amounts presented in the consolidated statement of financial condition.