Investment In Unconsolidated Affiliate (Narrative) (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2022	Mar. 31, 2021	Apr. 01, 2021
Investments in and Advances to Affiliates [Line Items]
Distributions received from LSV	$ 32,961	$ 28,774
Company's share in the earnings of LSV	$ 32,459	33,350
LSV Asset Management
Investments in and Advances to Affiliates [Line Items]
Ownership interest in LSV	38.70%		38.60%
Total investment in LSV	$ 52,778
Distributions received from LSV	32,961	28,774
Company's share in the earnings of LSV	$ 32,459	$ 33,350

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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