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Goodwill and Acquired Client Relationships (Tables) | 9 Months Ended
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Sep. 30, 2025
Goodwill and Intangible Assets Disclosure [Abstract] |
Schedule of Changes in Goodwill | The following table presents the changes in the Company’s consolidated Affiliates’ Goodwill:
|  | Goodwill
Balance, as of December 31, 2024 |  | $2,504.9
Foreign currency translation |  | 23.3
Balance, as of September 30, 2025 |  | $2,528.2
Schedule of Changes in the Components of Acquired Client Relationships | The following table presents the changes in the Company’s components of Acquired client relationships (net):
| Acquired Client Relationships (Net)
| Definite-lived |  | Indefinite-lived |  | Total
| Gross Book Value |  | Accumulated Amortization |  | Net Book Value |  | Net Book Value |  | Net Book Value
Balance, as of December 31, 2024 | $1,255.5 |  | $(1,075.2) |  | $180.3 |  | $1,597.5 |  | $1,777.8
Intangible amortization and impairments | — |  | (19.0) |  | (19.0) |  | (77.0) |  | (96.0)
Foreign currency translation | 10.6 |  | (10.6) |  | — |  | 21.5 |  | 21.5
Balance, as of September 30, 2025 | $1,266.1 |  | $(1,104.8) |  | $161.3 |  | $1,542.0 |  | $1,703.3

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- Definition Tabular disclosure of intangibles assets, in total and by major class, including the gross carrying amount and accumulated amortization. A major class is composed of intangible assets that can be grouped together because they are similar, either by their nature or by their use in the operations of a company. + References No definition available. + Details
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