Investment In Unconsolidated Affiliate (Narrative) (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018
Investments in and Advances to Affiliates [Line Items]
Distributions received from unconsolidated affiliate	$ 33,237	$ 45,617
Company's share in the earnings of equity method investee	$ 37,317	40,607
LSV Asset Management
Investments in and Advances to Affiliates [Line Items]
Equity method investment, ownership percentage	38.90%
Total investment in equity method investee	$ 56,422
Distributions received from unconsolidated affiliate	33,237	45,617
Company's share in the earnings of equity method investee	$ 37,317	$ 40,607

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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