Investment In Unconsolidated Affiliate (Narrative) (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Schedule of Equity Method Investments [Line Items]
Total investment in LSV	$ 44,645		$ 44,645
Distributions received from LSV			100,252	$ 103,504
Company's share in the earnings of LSV	$ 29,927	$ 26,654	$ 91,517	$ 88,926
L S V Asset Management
Schedule of Equity Method Investments [Line Items]
Ownership interest in LSV	38.60%		38.60%

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