Income Taxes - Reconciliation from Tax at U.S. Federal Statutory Rate to Company's Provision (Benefit) for Income Taxes (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Income Tax Disclosure [Abstract]
Tax at U.S. federal income tax rate	$ 1.7	$ 0.9	$ 31.1
State taxes, net of federal income tax effect	0.7	0.3	1.8
Other changes in tax rate	(0.2)	(0.2)	(10.6)
Outside basis difference	(11.5)
Foreign taxes	2.3	3.9	0.7
Global intangible low-taxed income	(0.8)	(2.1)	1.3
Valuation allowance	0.5	0.5	0.1
Tax credits and incentives	(2.0)	(2.5)	(2.6)
Impairment charges	14.5	29.0
Other	2.3	(0.3)	(0.8)
(Benefit)/Provision for income taxes	$ (19.9)	$ 29.5	$ 21.0