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v3.25.3

Goodwill and Acquired Client Relationships - Schedule of Changes in the Components of Acquired Client Relationships (Details) - USD ($) $ in Millions | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2025 | Sep. 30, 2024 | Sep. 30, 2025 | Sep. 30, 2024
Total |  |  |  |
Beginning balance, Net Book Value |  |  | $ 1,777.8 |
Intangible amortization and impairments | $ (6.3) | $ (7.3) | (96.0) | $ (21.8)
Ending balance, Net Book Value | 1,703.3 |  | 1,703.3 |
Acquired Client Relationships |  |  |  |
Total |  |  |  |
Beginning balance, Net Book Value |  |  | 1,777.8 |
Intangible amortization and impairments |  |  | 96.0 |
Foreign currency translation |  |  | 21.5 |
Ending balance, Net Book Value | 1,703.3 |  | 1,703.3 |
Acquired Client Relationships |  |  |  |
Indefinite-lived |  |  |  |
Beginning balance, Net Book Value |  |  | 1,597.5 |
Intangible amortization and impairments |  |  | (77.0) |
Foreign currency translation |  |  | 21.5 |
Ending balance, Net Book Value | 1,542.0 |  | 1,542.0 |
Acquired Client Relationships |  |  |  |
Definite-lived |  |  |  |
Beginning balance, Gross Book Value |  |  | 1,255.5 |
Beginning balance, Accumulated Amortization |  |  | (1,075.2) |
Beginning balance, Net Book Value |  |  | 180.3 |
Intangible amortization and impairments | (6.3) | $ (7.3) | (19.0) | $ (21.8)
Foreign currency translation, Gross Book Value |  |  | 10.6 |
Foreign currency translation, Accumulated Amortization |  |  | (10.6) |
Foreign currency translation, Net Book Value |  |  | 0.0 |
Ending balance, Gross Book Value | 1,266.1 |  | 1,266.1 |
Ending balance, Accumulated Amortization | (1,104.8) |  | (1,104.8) |
Ending balance, Net Book Value | $ 161.3 |  | $ 161.3 |

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