Long-Term Debt - Summary of Debt Refinancing Costs (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure [Abstract]
Gross cost at January 1	$ 1.8	$ 1.5
Capitalized in the year	0.0	0.3
Gross cost	1.8	1.8	$ 1.5
Accumulated amortization,Beginning Balance	(0.5)	(0.1)
Amortization in the year	(0.3)	(0.4)	(1.0)
Accumulated amortization,Ending balance	(0.8)	(0.5)	$ (0.1)
Deferred finance costs, net	$ 1.0	$ 1.3