Debt - Outstanding Debt Obligations (Detail) - USD ($) $ in Millions	Mar. 31, 2021	Dec. 31, 2020
Debt Instrument [Line Items]
Finance leases	$ 0.2	$ 0.3
Total gross debt	1,422.4	1,443.2
Less: debt discount and deferred financing costs	(17.5)	(18.5)
Total debt, net of debt discount and deferred financing costs	1,404.9	1,424.7
Less: current portion of long-term debt	(16.6)	(16.6)
Total long-term debt, net of unaccreted discount	1,388.3	1,408.1
Term Loan [Member]
Debt Instrument [Line Items]
Debt	1,010.0	1,030.0
Notes [Member]
Debt Instrument [Line Items]
Debt	400.0	400.0
Mortgages and Other [Member]
Debt Instrument [Line Items]
Debt	$ 12.2	$ 12.9