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Description of Business (Details) $ in Millions | 3 Months Ended
--- | ---
Mar. 31, 2024 USD ($) Segment | Mar. 31, 2023 USD ($)
Schedule of Equity Method Investments [Line Items] |  |
Number of business segments | Segment | 3 |
Net gain on asset dispositions | $ 36.2 | $ 47.1
Asset Impairment Charges | 0.0 | 1.2
Portfolio Investments and Capital Additions | 378.6 | 387.0
Rail International |  |
Schedule of Equity Method Investments [Line Items] |  |
Net gain on asset dispositions | 1.3 | 0.8
Asset Impairment Charges |  | 0.0
Portfolio Investments and Capital Additions | $ 49.9 | $ 81.1

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