Investment In Unconsolidated Affiliate (Statement of Operations) (Details) - LSV Asset Management - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Schedule of Equity Method Investments [Line Items]
Revenues	$ 99,996	$ 120,915
Net income	$ 76,897	$ 95,948

The amount of net income (loss) reported by an equity method investment of the entity.

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