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Investment In Unconsolidated Affiliate (Narrative) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021	Apr. 01, 2022	Mar. 31, 2022
Schedule of Equity Method Investments [Line Items]
Total investment in LSV	$ 39,012		$ 39,012
Distributions received from LSV			103,504	$ 110,559
Company's share in the earnings of LSV	$ 26,654	$ 35,005	$ 88,926	$ 103,420
L S V Asset Management
Schedule of Equity Method Investments [Line Items]
Ownership interest in LSV	38.60%		38.60%		38.60%	38.70%