STOCKHOLDERS' DEFICIT - Stock-based compensation (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Stock Based Compensation Expense
Stock-based compensation expense	$ 16.9	$ 22.0	$ 42.5
Total estimated unrecognized compensation cost related to nonvested stock-based compensation arrangements	$ 8.1
Weighted average period recognized	1 year 3 months 18 days
Board of director stock award expense
Stock Based Compensation Expense
Stock-based compensation expense	$ 1.3	1.0	0.9
Special awards expense
Stock Based Compensation Expense
Stock-based compensation expense	1.0	2.1	20.2
Equity classified awards
Stock Based Compensation Expense
Stock-based compensation expense	16.9	21.9	42.1
Restricted stock unit expense
Stock Based Compensation Expense
Stock-based compensation expense	13.4	12.3	14.3
Performance stock unit expense
Stock Based Compensation Expense
Stock-based compensation expense	$ 1.2	6.5	6.7
Liability classified awards
Stock Based Compensation Expense
Stock-based compensation expense		0.1	0.4
Restricted and performance stock unit expense
Stock Based Compensation Expense
Stock-based compensation expense		$ 0.1	$ 0.4

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section S45
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479983/718-10-S45-1

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SAB Topic 14.F)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479830/718-10-S99-1

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (h)(1)(i)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480429/718-10-50-2

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Amount of cost not yet recognized for nonvested award under share-based payment arrangement.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (i)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480429/718-10-50-2

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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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