Segment Information - Reconciliation (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Segment Reporting [Abstract]
Segment profit	$ 259.1	$ 292.0	$ 559.2	$ 593.3
General and administrative expenses	(23.5)	(32.2)	(53.9)	(83.6)
Loss on disposition of assets	(5.2)	(0.1)	(4.6)	(0.1)
Depreciation and amortization	(158.2)	(153.7)	(321.0)	(305.8)
Impairments	(1.5)	0.0	(354.5)	(186.5)
Loss on secured term loan receivable	0.0	(52.9)	0.0	(52.9)
Operating income (loss)	$ 70.7	$ 53.1	$ (174.8)	$ (35.6)