Segments - Holdings - Reconciliation of Net Income (Loss) to Adjusted EBITDA (Detail) - USD ($) $ in Millions		3 Months Ended						9 Months Ended
		Sep. 30, 2024	Jun. 30, 2024	Mar. 31, 2024	Sep. 30, 2023	Jun. 30, 2023	Mar. 31, 2023	Sep. 30, 2024	Sep. 30, 2023
Add (deduct):
Interest expense	[1]	$ 36.7			$ 38.1			$ 109.0	$ 112.0
Other income, net	[2]	(22.4)			(4.9)			(40.0)	(18.9)
Depreciation and amortization		49.1			51.9			148.3	159.6
Impairment of long-lived and other assets		0.0			2.0			0.0	12.1
(Gain) loss on disposal of assets and other		(0.1)			(6.1)			2.0	(8.8)
Loss on debt amendments and extinguishments		3.0			0.0			5.5	10.7
Non-cash rent expense		(2.6)			(4.8)			(10.2)	(13.2)
Share-based awards compensation expense		8.4			6.4			24.1	18.9
Adjusted EBITDA		220.5			196.8			433.3	514.5
CNK
Segment Reporting Information [Line Items]
Net income		188.9	$ 46.6	$ 25.3	91.2	$ 120.4	$ (2.5)	260.8	209.1
Add (deduct):
Income tax (benefit) expense		(42.7)			21.4			(71.3)	29.8
Interest expense		36.7			38.1			109.0	112.0
Cash distributions from equity investees								5.1	3.2
Depreciation and amortization		49.1			51.9			148.3	159.6
Impairment of long-lived and other assets		0.0			2.0			0.0	12.1
Loss on debt amendments and extinguishments		3.0			0.0			5.5	10.7
Non-cash rent expense								(10.2)	(13.2)
Share-based awards compensation expense								(24.1)	(18.9)
Other Cash Distributions From Equity Investees [Member]
Add (deduct):
Cash distributions from equity investees	[3]	$ 2.2			$ 1.6			$ 5.1	$ 3.2

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

[2] Includes interest income, foreign currency exchange and other related loss, interest expense - NCM, equity in income of affiliates and net gain on investment in NCMI.

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