Percentage of interest rate in cash.

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Percentage of paid in kind interest rate.

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The amount of gain loss on business interruption insurance recovery.

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Contractual interest rate for funds borrowed, under the debt agreement.

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Amount of net periodic benefit cost (credit) for defined benefit plan.

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Net Increase or Decrease in the fair value of the embedded derivative or group of embedded derivatives included in earnings in the period.

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Amount, before tax, of realized gain (loss) from foreign currency transaction.

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Difference between the fair value of payments made and the carrying amount of debt which is extinguished prior to maturity.

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Amount of income (loss) for proportionate share of equity method investee's income (loss).

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BASIS OF PRESENTATION - Other Expense (Details) - USD ($) $ in Millions					3 Months Ended		9 Months Ended		12 Months Ended
	May 11, 2026	Apr. 17, 2026	Aug. 06, 2025	Jul. 01, 2025	Sep. 30, 2026	Sep. 30, 2025	Sep. 30, 2026	Sep. 30, 2025	Dec. 31, 2025
Other Income:
Foreign currency transaction losses (gains)					$ (1.6)	$ 9.0	$ 7.0	$ (27.9)
Net periodic pension cost					0.5	0.3	1.5	0.9
(Gain)/Loss on extinguishment of debt						196.0	63.7	196.0
Debt modifications - third party fees			$ 2.1			2.1	0.3	2.1
Increase (Decrease) in fair value of bifurcated embedded derivative							2.0	52.1
Equity in earnings of non-consolidated entities					(2.6)	(1.6)	(9.3)	(4.5)
Business interruption insurance recoveries					(1.3)	(0.1)	(1.5)	(0.1)
Other financing costs					1.1		1.1
Total other expense					2.9	194.8	60.1	103.9
International Markets
Other Income:
Governmental assistance					$ (0.2)		$ (0.7)	$ (10.5)
Government Assistance, Nonoperating Income, Increase (Decrease), Statement of Income or Comprehensive Income [Extensible Enumeration]					Total other expense		Total other expense	Total other expense
Senior Secured Exchangeable Notes due 2030
Other Income:
(Gain)/Loss on extinguishment of debt	$ 33.0						$ 33.0
Increase (Decrease) in fair value of bifurcated embedded derivative						9.5	11.1	$ 9.5
Interest rate cash (as a percent)									1.50%
Odeon Senior Secured Notes due 2027
Other Income:
(Gain)/Loss on extinguishment of debt		$ 30.1					30.1
Stated interest rate (as a percent)									12.75%
Senior Subordinated Notes due 2026
Other Income:
(Gain)/Loss on extinguishment of debt						0.3		0.3
Senior Subordinated Notes due 2027
Other Income:
(Gain)/Loss on extinguishment of debt					$ 0.6		0.6
Stated interest rate (as a percent)									6.125%
Second Lien Notes due 2026
Other Income:
(Gain)/Loss on extinguishment of debt						(6.6)		(6.6)
6.00%/8.00% Cash/PIK Toggle Senior Secured Exchangeable Notes due 2030
Other Income:
(Gain)/Loss on extinguishment of debt				$ 103.3		103.3		103.3
Increase (Decrease) in fair value of bifurcated embedded derivative					$ (6.4)	1.4	$ (9.1)	$ 42.6
Interest rate cash (as a percent)							6.00%	6.00%	6.00%
PIK interest rate (as a percent)							8.00%	8.00%	8.00%
First Lien Notes due 2029
Other Income:
(Gain)/Loss on extinguishment of debt				$ 99.0		$ 99.0		$ 99.0
Stated interest rate (as a percent)					7.50%	7.50%	7.50%	7.50%	7.50%