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Goodwill and Acquired Client Relationships - Schedule of Changes in Acquired Client Relationships (Details) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2023 | Dec. 31, 2022 | Dec. 31, 2021
Intangible assets |  |  |
Impairment Of Intangible Asset Indefinite Lived Excluding Goodwill, Statement Of Income Or Comprehensive Income, Extensible Enumeration, Not Disclosed Flag | Indefinite-lived |  |
Net Book Value |  |  |
Beginning balance, net book value | $ 1,876.0 |  |
Intangible amortization and impairments | (48.3) | $ (51.6) | $ (35.7)
Ending balance, net book value | 1,812.4 | 1,876.0 |
Non-controlling interests: |  |  |
Net Book Value |  |  |
Finite-lived intangible assets deconsolidated | 3.5 |  |
Acquired client relationships |  |  |
Indefinite-lived |  |  |
Beginning balance, net book value | 1,590.6 | 1,630.3 |
Foreign currency translation | 16.6 | (37.2) |
Transfers, net book value | (4.1) |  |
Ending balance, net book value | 1,603.1 | 1,590.6 | 1,630.3
Net Book Value |  |  |
Intangible amortization and impairments |  | (2.5) |
Acquired client relationships |  |  |
Definite-lived |  |  |
Beginning balance, gross book value | 1,355.1 | 1,364.2 |
Beginning balance, accumulated amortization | (1,069.7) | (1,028.1) |
Beginning balance, net book value | 285.4 | 336.1 |
Intangible amortization and impairments | (48.3) | (49.1) |
Foreign currency translation, gross book value | 0.8 | (9.1) |
Foreign currency translation, accumulated depreciation | (0.5) | 7.5 |
Foreign currency translation, net book value | 0.3 | (1.6) |
Veritable Transaction, gross book value | (85.1) |  |
Veritable Transaction, accumulated amortization | 57.0 |  |
Veritable Transaction, net book value | (28.1) |  |
Transfers, gross book value | (10.3) |  |
Transfers, accumulated amortization | 10.3 |  |
Ending balance, gross book value | 1,260.5 | 1,355.1 | 1,364.2
Ending balance, accumulated amortization | (1,051.2) | (1,069.7) | (1,028.1)
Ending balance, net book value | 209.3 | 285.4 | 336.1
Net Book Value |  |  |
Beginning balance, net book value | 1,876.0 | 1,966.4 |
Veritable Transaction | (28.1) |  |
Intangible amortization and impairments | (48.3) | (51.6) |
Foreign currency translation | 16.9 | (38.8) |
Transfers, net book value | (4.1) |  |
Ending balance, net book value | 1,812.4 | $ 1,876.0 | $ 1,966.4
Acquired client relationships | Non-controlling interests: |  |  |
Net Book Value |  |  |
Finite-lived intangible assets deconsolidated | $ 6.7 |  |

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