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Goodwill And Intangible Assets (Components Of Intangible Assets) (Details) - USD ($) $ in Thousands | Dec. 31, 2024 | Dec. 31, 2023
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Schedule of Indefinite-Lived And Finite-Lived Intangible Assets [Line Items] |  |
Intangible assets, gross carrying amount | $ 2,898,994 | $ 2,860,728
Intangible assets, accumulated amortization | (1,439,374) | (1,272,044)
Customer Relationships [Member] |  |
Schedule of Indefinite-Lived And Finite-Lived Intangible Assets [Line Items] |  |
Intangible assets, gross carrying amount | 1,488,796 | 1,450,503
Intangible assets, accumulated amortization | (699,550) | (600,724)
Investment Management Agreements [Member] |  |
Schedule of Indefinite-Lived And Finite-Lived Intangible Assets [Line Items] |  |
Intangible assets, gross carrying amount | 464,000 | 464,000
Intangible assets, accumulated amortization | (178,727) | (149,560)
Broker and Agent Relationships [Member] |  |
Schedule of Indefinite-Lived And Finite-Lived Intangible Assets [Line Items] |  |
Intangible assets, gross carrying amount | 295,694 | 297,693
Intangible assets, accumulated amortization | (182,139) | (168,586)
Trade Names [Member] |  |
Schedule of Indefinite-Lived And Finite-Lived Intangible Assets [Line Items] |  |
Intangible assets, gross carrying amount | 305,381 | 293,270
Intangible assets, accumulated amortization | (157,494) | (138,040)
Technology [Member] |  |
Schedule of Indefinite-Lived And Finite-Lived Intangible Assets [Line Items] |  |
Intangible assets, gross carrying amount | 113,187 | 113,248
Intangible assets, accumulated amortization | (107,727) | (100,781)
Insurance Licenses [Member] |  |
Schedule of Indefinite-Lived And Finite-Lived Intangible Assets [Line Items] |  |
Intangible assets, gross carrying amount | 72,333 | 72,333
Intangible assets, accumulated amortization | 0 | 0
Other [Member] |  |
Schedule of Indefinite-Lived And Finite-Lived Intangible Assets [Line Items] |  |
Intangible assets, gross carrying amount | 159,603 | 169,681
Intangible assets, accumulated amortization | $ (113,737) | $ (114,353)

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