Investments Of Operating Entities And Consolidated Funds - Consolidated Funds - Indirect Concentration of the Underlying Investments Held by Consolidated Funds (Details) - Equity Securities - Linkem - ITALY - Wireless Broadband - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Investment Holdings [Line Items]
Percentage of Stockholders' Equity	9.36%	9.53%
Market Value	$ 73,437	$ 77,142