Investment In Unconsolidated Affiliate (Narrative) (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2023	Mar. 31, 2022
Schedule of Equity Method Investments [Line Items]
Total investment in LSV	$ 55,041
Distributions received from LSV	29,219	$ 32,961
Company's share in the earnings of LSV	$ 28,879	$ 32,459
L S V Asset Management
Schedule of Equity Method Investments [Line Items]
Ownership interest in LSV	38.60%

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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