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Goodwill and Acquired Client Relationships (Tables) | 6 Months Ended
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Jun. 30, 2018
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) in the Consolidated Condensed Balance Sheets:
|  | Goodwill
|  | Total
Balance, as of December 31, 2017 |  | $ | 2,662.5 |
Foreign currency translation |  | (13.9 | )
Balance, as of June 30, 2018 |  | $ | 2,648.6 |
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, 2017 | $ | 1,295.5 |  |  | $ | (874.5 | ) |  | $ | 421.0 |  |  | $ | 1,028.7 |  |  | $ | 1,449.7 |
Intangible amortization and impairments | — |  |  | (46.4 | ) |  | (46.4 | ) |  | — |  |  | (46.4 | )
Foreign currency translation | (1.2 | ) |  | — |  |  | (1.2 | ) |  | (8.8 | ) |  | (10.0 | )
Balance, as of June 30, 2018 | $ | 1,294.3 |  |  | $ | (920.9 | ) |  | $ | 373.4 |  |  | $ | 1,019.9 |  |  | $ | 1,393.3 |

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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://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 20 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 20 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13854-109267 + Details
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