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Investments in Affiliated Companies (Share of Affiliate Earnings) (Details 2) - USD ($) $ in Millions | 12 Months Ended
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Dec. 31, 2024 | Dec. 31, 2023 | Dec. 31, 2022
Pre tax share of affiliates earnings by segment |  |  |
Share of affiliates' earnings (pre-tax) | $ 108.3 | $ 98.1 | $ 45.9
Provision for Income Taxes, Equity Method Investment | (25.5) | (25.7) | (12.3)
Share of Affiliates' Earnings | 82.8 | 72.4 | 33.6
Rail North America [Member] |  |  |
Pre tax share of affiliates earnings by segment |  |  |
Share of affiliates' earnings (pre-tax) | 0.0 | (0.6) | 0.5
Rail International [Member] |  |  |
Pre tax share of affiliates earnings by segment |  |  |
Share of affiliates' earnings (pre-tax) | 0.0 | 0.0 | 0.0
Portfolio Management [Member] |  |  |
Pre tax share of affiliates earnings by segment |  |  |
Share of affiliates' earnings (pre-tax) | $ 108.3 | $ 98.7 | $ 45.4

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