SEGMENTS - HOLDINGS - Reconciliation of Net Income to Adjusted EBITDA (Detail) - USD ($) $ in Millions		12 Months Ended
		Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Segment Reporting Information [Line Items]
Net (loss) income		$ 191.5	$ (268.0)	$ (422.2)
Add (deduct):
Income tax benefit (expense)		29.9	3.0	(16.8)
Interest expense	[1]	150.4	155.3	149.7
Other expense (income), net	[2]	(19.6)	23.6	43.5
Depreciation and amortization		209.5	238.2	265.4
Impairment of long-lived and other assets		16.6	174.1	20.8
Restructuring costs		0.0	(0.5)	(1.0)
(Gain) loss on disposal of assets and other		(7.7)	(6.8)	8.0
Loss on debt extinguishment and refinancing		10.7	0.0	6.5
Non-cash rent expense		(17.9)	(10.8)	(3.4)
Share based awards compensation expense		25.0	21.5	29.3
Adjusted EBITDA	[3]	594.1	336.5	80.0
Other Cash Distributions From Equity Investees [Member]
Add (deduct):
Cash distributions from equity investees	[4]	$ 5.7	$ 6.9	$ 0.2

[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 and equity in income (loss) of affiliates and unrealized gain on investment in NCMI. Excludes distributions from NCM and DCIP.

[3] Distributions from equity investees are reported entirely within the U.S. operating segment

[4] Reflects cash distributions received from equity investees that were recorded as a reduction of the respective investment balances (see Note 10). These distributions are reported entirely within the U.S. operating segment.