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v3.25.2

Goodwill and Acquired Client Relationships - Schedule of Changes in the Components of Acquired Client Relationships (Details) - USD ($) $ in Millions | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2025 | Jun. 30, 2024 | Jun. 30, 2025 | Jun. 30, 2024
Total |  |  |  |
Beginning balance, Net Book Value |  |  | $ 1,777.8 |
Intangible amortization and impairments | $ (6.3) | $ (7.3) | (89.6) | $ (14.5)
Ending balance, Net Book Value | 1,716.1 |  | 1,716.1 |
Acquired Client Relationships |  |  |  |
Total |  |  |  |
Beginning balance, Net Book Value |  |  | 1,777.8 |
Intangible amortization and impairments |  |  | 89.6 |
Foreign currency translation |  |  | 27.9 |
Ending balance, Net Book Value | 1,716.1 |  | 1,716.1 |
Acquired Client Relationships |  |  |  |
Indefinite-lived |  |  |  |
Beginning balance, Net Book Value |  |  | 1,597.5 |
Intangible amortization and impairments |  |  | (77.0) |
Foreign currency translation |  |  | 28.1 |
Ending balance, Net Book Value | 1,548.6 |  | 1,548.6 |
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) | (12.6) | $ (14.5)
Foreign currency translation, Gross Book Value |  |  | 14.5 |
Foreign currency translation, Accumulated Amortization |  |  | (14.7) |
Foreign currency translation, Net Book Value |  |  | (0.2) |
Ending balance, Gross Book Value | 1,270.0 |  | 1,270.0 |
Ending balance, Accumulated Amortization | (1,102.5) |  | (1,102.5) |
Ending balance, Net Book Value | $ 167.5 |  | $ 167.5 |

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