Income Taxes - Narrative (Details) - USD ($) $ in Millions		1 Months Ended	3 Months Ended		9 Months Ended
		Feb. 07, 2019	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Income Tax Disclosure [Abstract]
Effective tax rate (as a percent)		26.70%	37.20%	30.10%	48.80%	20.40%
Income tax benefit	[1]	$ 27.5	$ 9.3	$ 24.0	$ 111.1	$ 84.1
Loss before benefit for income taxes and equity in net income of affiliates	[1]	$ 102.8	$ 24.9	$ 79.8	227.8	$ 412.9
Net benefit from CARES Act					$ 57.8

[1] See Note 1 "Basis of Presentation" for further discussion.