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Investments in Affiliated Companies (Future Debt Maturities) (Details 8) - USD ($) $ in Millions	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Schedule of Equity Method Investments [Line Items]
Investments in Affiliated Companies	$ 588.4	$ 584.7	$ 512.6
2016	363.7
2017	500.0
2018	533.1
2019	527.4
2020	461.4
Thereafter	3,544.4
Total debt principal	5,930.0	5,358.5
RRPF Joint Ventures [Member]
Schedule of Equity Method Investments [Line Items]
2016	364.2
2017	399.6
2018	164.1
2019	210.6
2020	465.6
Thereafter	1,529.9
Total debt principal	$ 3,134.0
Rail North America [Member]
Schedule of Equity Method Investments [Line Items]
Investments in Affiliated Companies		$ 0.0	$ 0.2