SEGMENTS - HOLDINGS - Reconciliation of Net Income to Adjusted EBITDA (Detail) - USD ($) $ in Millions		12 Months Ended
		Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Segment Reporting Information [Line Items]
Net (loss) income		$ 312.9	$ 191.5	$ (268.0)
Add (deduct):
Income tax (benefit) expense		(60.1)	29.9	3.0
Interest expense	[1]	144.0	150.4	155.3
Other expense (income), net	[2]	(44.4)	(19.6)	23.6
Depreciation and amortization		197.5	209.5	238.2
Impairment of long-lived and other assets		1.5	16.6	174.1
Restructuring costs		0.0	0.0	(0.5)
(Gain) loss on disposal of assets and other		1.6	(7.7)	(6.8)
Loss on debt amendments and extinguishments		6.9	10.7	0.0
Non-cash rent expense		(12.5)	(17.9)	(10.8)
Share-based awards compensation expense		33.5	25.0	21.5
Adjusted EBITDA		590.2	594.1	336.5
Other Cash Distributions From Equity Investees [Member]
Add (deduct):
Cash distributions from equity investees	[3]	$ 9.3	$ 5.7	$ 6.9

[1] Includes amortization of debt issuance costs, amortization of original issue discount, and amortization of accumulated (gains) losses for amended swap agreements.

[2] Includes interest income, foreign currency exchange and other related loss, interest expense – NCM, equity in income (loss) of affiliates and net gain on investment in NCMI. Excludes distributions from DCIP.

[3] Reflects cash distributions received from equity investees that were recorded as a reduction of the respective investment balances (see Note 9). These distributions are reported entirely within the U.S. reportable segment.