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Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
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Amount of cost not yet recognized for nonvested award under share-based payment arrangement.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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STOCKHOLDERS' DEFICIT - Stock-based compensation (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2025	Jun. 30, 2024	Jun. 30, 2025	Jun. 30, 2024
Stock Based Compensation Expense
Stock-based compensation expense	$ 6.0	$ 4.5	$ 11.7	$ 8.8
Total estimated unrecognized compensation cost related to nonvested stock-based compensation arrangements	20.1		$ 20.1
Weighted average period recognized			1 year
Board of director stock award expense
Stock Based Compensation Expense
Stock-based compensation expense		1.0	$ 1.3	1.0
Special award
Stock Based Compensation Expense
Stock-based compensation expense			1.0	2.1
Equity classified awards
Stock Based Compensation Expense
Stock-based compensation expense	6.0	4.4	11.7	8.7
Restricted stock unit expense
Stock Based Compensation Expense
Stock-based compensation expense	3.6	2.7	6.2	4.8
Performance stock unit expense
Stock Based Compensation Expense
Stock-based compensation expense	$ 2.4	0.7	$ 3.2	0.8
Liability classified awards
Stock Based Compensation Expense
Stock-based compensation expense		0.1		0.1
Restricted and performance stock unit expense
Stock Based Compensation Expense
Stock-based compensation expense		$ 0.1		$ 0.1