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Equity Method Investments in Affiliates - Change in Equity Method Investments in Affiliates (Details) - USD ($) $ in Millions | 12 Months Ended
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Dec. 31, 2021 | Dec. 31, 2020 | Dec. 31, 2019
Change in Equity Method Investments in Affiliates [Roll Forward] |  |  |
Balance, beginning of period | $ 2,074.8 |  |
Distributions of earnings | (337.5) | $ (236.8) | $ (252.4)
Balance, end of period | 2,134.4 | 2,074.8 |
Equity Method Investee |  |  |
Change in Equity Method Investments in Affiliates [Roll Forward] |  |  |
Balance, beginning of period | 2,074.8 | 2,195.6 |
Investments in Affiliates | 147.3 | 128.7 |
Earnings | 417.5 | 288.6 |
Intangible amortization and impairments | (175.0) | (332.0) |
Distributions of earnings | (337.5) | (236.8) |
Return of capital | (4.4) | 0.0 |
Foreign currency translation | 12.5 | 5.1 |
Other | (0.8) | 25.6 |
Balance, end of period | $ 2,134.4 | $ 2,074.8 | $ 2,195.6

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