Investment in Unconsolidated Affiliates (Narrative) (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020	Apr. 01, 2022	Mar. 31, 2021
Investments in and Advances to Affiliates [Line Items]
Company's share in the earnings of LSV	$ 120,667	$ 137,572	$ 117,134
Distributions received from LSV	$ 120,849	131,170	125,534
LSV Asset Management
Investments in and Advances to Affiliates [Line Items]
Ownership interest in LSV	38.60%			38.60%	38.70%
Total investment in LSV	$ 104,673
Company's share in the earnings of LSV	120,667	137,572	117,134
Distributions received from LSV	$ 120,849	$ 131,170	$ 125,534

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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