Segment Information - Reconciliation (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Segment Reporting [Abstract]
Segment profit	$ 284.7	$ 289.3	$ 843.9	$ 882.6
General and administrative expenses	(25.7)	(38.5)	(79.6)	(122.1)
Gain (loss) on disposition of assets	1.8	3.0	(2.8)	2.9
Depreciation and amortization	(160.3)	(157.3)	(481.3)	(463.1)
Impairments	0.0	0.0	(354.5)	(186.5)
Loss on secured term loan receivable	0.0	0.0	0.0	(52.9)
Operating income (loss)	$ 100.5	$ 96.5	$ (74.3)	$ 60.9