Investments in Affiliated Companies (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Alpha Partners Leasing Limited [Domain]
Equity Method Investment, Summarized Financial Information. Revenue.	$ 104.0	$ 94.1
Equity Method Investment, Summarized Financial Information, Other Expenses	(86.4)	(71.3)
Equity Method Investment, Summarized Financial Information, Gains (Losses)	22.3	6.7
RRPF Joint Ventures [Member]
Equity Method Investment, Summarized Financial Information, Net Income (Loss)	$ 32.3	$ 23.8