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Investments in Affiliated Companies (Investments and Distributions) (Details 3) - USD ($) $ in Millions | 12 Months Ended
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Dec. 31, 2024 | Dec. 31, 2023 | Dec. 31, 2022
Schedule of Equity Method Investments [Line Items] |  |  |
Asset Impairment Charges | $ 0.0 | $ 1.5 | $ 48.9
Proceeds from Equity Method Investment, Distribution | 50.0 | 25.0 | 46.3
Rail North America [Member] |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |
Asset Impairment Charges |  | 0.0 | 0.0
Rail International [Member] |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |
Asset Impairment Charges | 0.0 | 0.3 | 14.6
Portfolio Management [Member] |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |
Asset Impairment Charges | 0.0 | 1.2 | 34.3
Proceeds from Equity Method Investment, Distribution | $ 50.0 | $ 25.0 | $ 46.3

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