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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, 2023 | Dec. 31, 2022 | Dec. 31, 2021
Change in Equity Method Investments in Affiliates [Roll Forward] |  |  |
Balance, beginning of period | $ 2,139.5 |  |
Distributions of earnings | (490.8) | $ (393.5) | $ (337.5)
Return of capital | (0.2) | (0.8) | (4.4)
Balance, end of period | 2,288.5 | 2,139.5 |
Equity Method Investee |  |  |
Change in Equity Method Investments in Affiliates [Roll Forward] |  |  |
Balance, beginning of period | 2,139.5 | 2,134.4 |
Investments in Affiliates | 349.8 | 326.1 |
BPEA | 0.0 | (150.6) |
Earnings | 375.6 | 497.2 |
Intangible amortization and impairments | (95.6) | (159.1) |
Distributions of earnings | (492.1) | (394.7) |
Return of capital | (0.2) | (0.8) |
Foreign currency translation | 29.3 | (68.5) |
Other | (17.8) | (44.5) |
Balance, end of period | $ 2,288.5 | $ 2,139.5 | $ 2,134.4

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