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Equity Method Investments in Affiliates - Change in Equity Method Investments (Details) - USD ($) $ in Millions | 9 Months Ended
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Sep. 30, 2021 | Sep. 30, 2020
Change in Equity Method Investments in Affiliates [Roll Forward] |  |
Balance, as of December 31, 2020 | $ 2,074.8 |
Distributions of earnings | (288.1) | $ (197.2)
Return of capital | (3.4) | $ 0.0
Balance, as of September 30, 2021 | 2,085.2 |
Equity Method Investee |  |
Change in Equity Method Investments in Affiliates [Roll Forward] |  |
Balance, as of December 31, 2020 | 2,074.8 |
Investments in Affiliates | 144.3 |
Earnings | 218.9 |
Intangible amortization and impairments | (93.8) |
Distributions of earnings | (288.1) |
Return of capital | (3.4) |
Foreign currency translation | 25.8 |
Other | 6.7 |
Balance, as of September 30, 2021 | $ 2,085.2 |

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