Background and Basis of Presentation - Summary of EPS, Weighted Average Common Shares and Potential Common Shares Outstanding (Detail) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Numerator:
Income (loss) from continuing operations	$ (262.1)	$ 29.8
Loss from discontinued operations, net of tax	(97.1)	(26.4)
Net income (loss)	(359.2)	3.4
Dividends on Series A convertible preferred stock	(16.0)	(15.1)
Net loss attributable to common stockholders	$ (375.2)	$ (11.7)
Denominator:
Weighted average common shares outstanding - basic	212.3	208.9
Dilutive effect of as-if converted Series A convertible preferred stock	0.0	0.0
Dilutive effect of equity-based awards	0.0	3.2
Weighted average common shares outstanding - diluted	212.3	212.1
Basic:
Earnings (loss) from continuing operations per share	$ (1.31)	$ 0.07
Loss from discontinued operations per share	(0.46)	(0.12)
Loss per share	(1.77)	(0.05)
Diluted:
Earnings (loss) from continuing operations per share	(1.31)	0.07
Loss from discontinued operations per share	(0.46)	(0.13)
Loss per share	$ (1.77)	$ (0.06)