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Investments in Affiliated Companies (Future Debt Maturities) (Details 8) - USD ($) $ in Millions	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Schedule of Equity Method Investments [Line Items]
Investments in Affiliated Companies	$ 627.0	$ 575.1	$ 588.4
2016	526.3
2017	520.8
2018	611.9
2019	458.4
2020	735.0
Thereafter	4,598.2
Total debt principal	7,450.6	$ 6,492.2
RRPF Joint Ventures [Member]
Schedule of Equity Method Investments [Line Items]
2016	173.5
2017	286.0
2018	465.6
2019	317.9
2020	438.0
Thereafter	774.0
Total debt principal	$ 2,455.0
Rail North America [Member]
Schedule of Equity Method Investments [Line Items]
Investments in Affiliated Companies			$ 0.3