Investment In Unconsolidated Affiliate (Narrative) (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019	Apr. 01, 2020
Investments in and Advances to Affiliates [Line Items]
Distributions received from unconsolidated affiliate			$ 84,502	$ 77,288
Company's share in the earnings of equity method investee	$ 28,276	$ 37,832	$ 58,183	75,149
LSV Asset Management
Investments in and Advances to Affiliates [Line Items]
Equity method investment, ownership percentage	38.80%		38.80%		38.90%
Total investment in equity method investee	$ 41,094		$ 41,094
Distributions received from unconsolidated affiliate			84,502	77,288
Company's share in the earnings of equity method investee	$ 28,276	$ 37,832	$ 58,183	$ 75,149

Amount of distribution received from equity method investee for return on investment, classified as operating activities. Excludes distribution for return of investment, classified as investing activities.

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