Investment in and Advances to Unconsolidated Affiliates - Affiliate Balance Sheet (Details) - USD ($) $ in Millions	Sep. 30, 2020	Dec. 31, 2019
Investments in and Advances to Affiliates, Affiliate Balance Sheet [Abstract]
Current assets	$ 151.3	$ 64.0
Property and equipment, net	270.4	256.1
Other assets, net	246.3	240.1
Total assets	668.0	560.2
Current liabilities	119.6	73.3
Long-term debt	783.0	745.0
Other liabilities	42.9	20.6
Members' deficit	(277.5)	(278.7)
Total liabilities and members' deficit	$ 668.0	$ 560.2