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Goodwill and Acquired Client Relationships (Tables) | 12 Months Ended
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Dec. 31, 2023
Goodwill and Intangible Assets Disclosure [Abstract] |
Schedule of Changes in Goodwill | The following tables present the changes in the Company’s consolidated Affiliates’ Goodwill and components of Acquired client relationships (net):
|  | Goodwill
|  | 2022 |  | 2023
Balance, beginning of period |  | $ | 2,689.2 |  |  | $ | 2,648.7 |
Veritable Transaction(1) |  | — |  |  | (136.5) |
Foreign currency translation |  | (40.5) |  |  | 16.5 |
Other |  | — |  |  | (5.1) |
Balance, end of period |  | $ | 2,648.7 |  |  | $ | 2,523.6 |
___________________________ (1)Represents Goodwill allocated to Veritable as of the closing date, including $3.5 million attributable to the non-controlling interests.
Schedule of Changes in the Components of Acquired Client Relationships | As of September 30, 2023, the Company completed its annual impairment assessment on goodwill and no impairment was indicated.
|  | 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, 2021 |  | $ | 1,364.2 |  |  | $ | (1,028.1) |  |  | $ | 336.1 |  |  | $ | 1,630.3 |  |  | $ | 1,966.4 |
Intangible amortization and impairments |  | — |  |  | (49.1) |  |  | (49.1) |  |  | (2.5) |  |  | (51.6) |
Foreign currency translation |  | (9.1) |  |  | 7.5 |  |  | (1.6) |  |  | (37.2) |  |  | (38.8) |
Balance, as of December 31, 2022 |  | $ | 1,355.1 |  |  | $ | (1,069.7) |  |  | $ | 285.4 |  |  | $ | 1,590.6 |  |  | $ | 1,876.0 |
Veritable Transaction(1) |  | (85.1) |  |  | 57.0 |  |  | (28.1) |  |  | — |  |  | (28.1) |
Intangible amortization and impairments |  | — |  |  | (48.3) |  |  | (48.3) |  |  | — |  |  | (48.3) |
Foreign currency translation |  | 0.8 |  |  | (0.5) |  |  | 0.3 |  |  | 16.6 |  |  | 16.9 |
Transfers(2) |  | (10.3) |  |  | 10.3 |  |  | — |  |  | (4.1) |  |  | (4.1) |
Balance, as of December 31, 2023 |  | $ | 1,260.5 |  |  | $ | (1,051.2) |  |  | $ | 209.3 |  |  | $ | 1,603.1 |  |  | $ | 1,812.4 |
___________________________ (1)Represents acquired client relationships attributable to Veritable as of the closing date, including $6.7 million attributable to the non-controlling interests. (2)Transfers include acquired client relationships at Affiliates that were deconsolidated during the period.

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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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