Investments of Operating Entities and Consolidated Funds - Operating Entities - Equity Method Investment - Narrative (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Schedule of Equity Method Investments [Line Items]
Other than Temporary Impairment Losses, Investments	$ 7,300	$ 0
Net Gains (Losses) on Securities, Derivatives and Other Investments
Schedule of Equity Method Investments [Line Items]
Income (Loss) from Equity Method Investments	$ 40	$ 16,300
Minimum
Schedule of Equity Method Investments [Line Items]
Equity Method Investment, Ownership Percentage	15.00%
Maximum
Schedule of Equity Method Investments [Line Items]
Equity Method Investment, Ownership Percentage	55.00%

The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

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The amount by which the fair value of an investment is less than the amortized cost basis or carrying amount of that investment at the balance sheet date and the decline in fair value is deemed to be other than temporary, before considering whether or not such amount is recognized in earnings or other comprehensive income.

+ References

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Amount of income (loss) for proportionate share of equity method investee's income (loss).

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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No definition available.

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