Debt - Component of Debt (Detail) - USD ($) $ in Millions	Dec. 31, 2023	Dec. 31, 2022
Debt Instrument [Line Items]
Other indebtedness	$ 0.0	$ 0.8
Unamortized original issue discount and debt issuance costs	(35.1)	(50.3)
Debt	6,720.0	7,079.6
Less: current portion of long-term debt	51.5	55.7
Long-term debt	6,668.5	7,023.9
Secured Debt [Member] | Senior Secured Credit Facilities [Member]
Debt Instrument [Line Items]
Long-term debt gross	4,755.1	5,129.1
Senior Notes [Member]
Debt Instrument [Line Items]
Long-term debt gross	2,000.0
Senior Notes [Member] | 5.5% Senior Notes due 2027 [Member]
Debt Instrument [Line Items]
Long-term debt gross	$ 2,000.0	$ 2,000.0