Earnings per Share (EPS) - Calculation of Basic and Diluted EPS (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
EPS numerator:
Loss from continuing operations, net of income taxes	$ (77.7)	$ (129.3)
Less: Net income (loss) attributable to noncontrolling interests	0.4	(1.8)
Loss from continuing operations attributable to common stockholders	(78.1)	(127.5)
Loss from discontinued operations, net of income taxes	(2.0)	(2.2)
Net loss attributable to common stockholders	$ (80.1)	$ (129.7)
EPS denominator:
Weighted average shares outstanding — basic and diluted	98.4	97.2
Basic EPS attributable to common stockholders:
Basic loss per share	$ (0.81)	$ (1.33)
Basic and diluted EPS attributable to common stockholders:
(Loss) income from continuing operations (in dollars per share)	(0.79)	(1.31)
Loss from discontinued operations (in dollars per share)	(0.02)	(0.02)
Net loss attributable to common stockholders	$ (0.81)	$ (1.33)