Percentage of interest rate in cash.

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Percentage of paid in kind interest rate.

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Amount of fees to third party incurred in connection with the modification of debt.

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The amount of gain loss on business interruption insurance recovery.

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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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Indicates line item in statement of income or comprehensive income that includes increase (decrease) in income from government assistance, classified as nonoperating.

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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 (Income) (Details) - USD ($) $ in Millions			3 Months Ended		6 Months Ended		12 Months Ended
	May 11, 2026	Apr. 17, 2026	Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025	Dec. 31, 2025
Other Income:
Foreign currency transaction losses (gains)			$ (0.4)	$ (23.9)	$ 8.6	$ (36.9)
Net periodic pension cost			0.5	0.3	1.0	0.6
Loss (gain) on extinguishment of debt					63.1
Debt modifications - third party fees					0.3
Bifurcated embedded derivative, increase (decrease) to Net Earnings (Loss)					(8.4)	(41.2)
Equity in earnings of non-consolidated entities			(4.0)	(2.1)	(6.7)	(2.9)
Business interruption insurance recoveries			(0.2)		(0.2)
Total other expense (income)			109.6	(32.1)	57.2	(90.9)
International Markets
Other Income:
Governmental assistance			$ (0.5)	$ (10.3)	$ (0.5)	$ (10.5)
Government Assistance, Nonoperating Income, Increase (Decrease), Statement of Income or Comprehensive Income [Extensible Enumeration]			Total other expense (income)	Total other expense (income)	Total other expense (income)	Total other expense (income)
Senior Secured Exchangeable Notes due 2030
Other Income:
Loss (gain) on extinguishment of debt	$ 33.0		$ 33.0		$ 33.0
Bifurcated embedded derivative, increase (decrease) to Net Earnings (Loss)			41.3		(11.1)
Interest rate cash (as a percent)							1.50%
Odeon Senior Secured Notes 2027
Other Income:
Loss (gain) on extinguishment of debt		$ 30.1	30.1		30.1
6.00%/8.00% Cash/PIK Toggle Senior Secured Exchangeable Notes due 2030
Other Income:
Bifurcated embedded derivative, increase (decrease) to Net Earnings (Loss)			$ 9.8	$ 3.9	$ 2.7	$ (41.2)
Interest rate cash (as a percent)			6.00%	6.00%	6.00%	6.00%	6.00%
PIK interest rate (as a percent)			8.00%	8.00%	8.00%	8.00%	8.00%