BASIS OF PRESENTATION - Other Expense (Income) (Details) - USD ($) $ in Millions	3 Months Ended	12 Months Ended
Mar. 31, 2026	Mar. 31, 2025	Dec. 31, 2025
Other Income:
Foreign currency transaction (gains) losses	$ 9.0	$ (13.0)
Governmental assistance		$ (0.2)
Government Assistance, Nonoperating Income, Increase (Decrease), Statement of Income or Comprehensive Income [Extensible Enumeration]		Total other expense (income)
Net periodic pension cost	0.5	$ 0.3
Debt modifications - third party fees	0.3
Bifurcated embedded derivative, (Increase) Decrease to Net Earnings (Loss)	(59.5)	(45.1)
Equity in earnings of non-consolidated entities	(2.7)	(0.8)
Total other expense (income)	(52.4)	(58.8)
6.00%/8.00% Cash/PIK Toggle Senior Secured Exchangeable Notes due 2030
Other Income:
Bifurcated embedded derivative, (Increase) Decrease to Net Earnings (Loss)	$ (7.1)	$ (45.1)
Interest rate cash (as a percent)	6.00%	6.00%	6.00%
PIK interest rate (as a percent)	8.00%	8.00%	8.00%
New exchangeable notes
Other Income:
Bifurcated embedded derivative, (Increase) Decrease to Net Earnings (Loss)	$ (52.4)
Interest rate cash (as a percent)	1.50%		1.50%

Percentage of interest rate in cash.

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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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