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Equity Method Investments in Affiliates - Financial Information for Affiliates Accounted for Under the Equity Method (Details) - USD ($) $ in Millions | 12 Months Ended
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Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017
Equity Method Investments and Joint Ventures [Abstract] |  |  |  |  |
Revenue | [1] | $ 2,760.9 |  | $ 3,231.7 | $ 3,126.3
Net income |  | 1,061.3 | [1] | 1,286.1 | $ 2,182.7
Assets |  | 2,718.5 |  | 2,730.4 |
Liabilities and Non-controlling interests |  | $ 1,212.7 |  | $ 1,235.1 |
[1] | Revenue and net income include asset and performance based fees, the impact of consolidated sponsored investment products and investments in new Affiliates for the full-year, regardless of the date of the Company’s investment.

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