Investments in Joint Ventures - Schedule of results of operations of the joint ventures (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Operating Revenue and Expenses
Revenues Joint Venture	$ 285.5	$ 266.1
Expenses	154.6	145.3
Excess of revenues over expenses	$ 130.9	$ 120.8