Amount of investment in equity method investee and investment in and advance to affiliate.

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Investments in Affiliated Companies (Future Debt Maturities) (Details 8) - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Schedule of Equity Method Investments [Line Items]
Investments in Affiliated Companies	$ 584.7	$ 512.6	$ 464.5
2016	600.0
2017	372.2
2018	250.0
2019	550.4
2020	544.3
Thereafter	3,041.6
Total debt principal	5,358.5	4,813.9
RRPF Joint Ventures [Member]
Schedule of Equity Method Investments [Line Items]
2016	203.3
2017	362.0
2018	389.7
2019	293.6
2020	210.6
Thereafter	1,995.5
Total debt principal	3,454.7
Rail North America [Member]
Schedule of Equity Method Investments [Line Items]
Investments in Affiliated Companies		0.2	$ 0.2
Rail North America [Member] \| Adler Funding Llc [Member]
Schedule of Equity Method Investments [Line Items]
Investments in Affiliated Companies	$ 0.0	$ 0.2