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Goodwill and Acquired Client Relationships (Tables) | 3 Months Ended
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Mar. 31, 2021
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
Balance, as of December 31, 2020 |  | $ | 2,661.4 |
Foreign currency translation |  | 4.8 |
Balance, as of March 31, 2021 |  | $ | 2,666.2 |
Schedule of Changes in the Components of Acquired Client Relationships |
| 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, 2020 | $ | 1,166.6 |  |  | $ | (1,026.8) |  |  | $ | 139.8 |  |  | $ | 909.0 |  |  | $ | 1,048.8 |
Intangible amortization and impairments | — |  |  | (7.5) |  |  | (7.5) |  |  | — |  |  | (7.5) |
Foreign currency translation | 1.4 |  |  | (1.2) |  |  | 0.2 |  |  | 2.8 |  |  | 3.0 |
Balance, as of March 31, 2021 | $ | 1,168.0 |  |  | $ | (1,035.5) |  |  | $ | 132.5 |  |  | $ | 911.8 |  |  | $ | 1,044.3 |

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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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- Definition Tabular disclosure of goodwill by reportable segment and in total which includes a rollforward schedule. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 20 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=121556970&loc=d3e13816-109267 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 20 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=121556970&loc=d3e13854-109267 + Details
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