STOCKHOLDERS' DEFICIT - RSU, PSU activity (Details) - USD ($) $ / shares in Units, $ in Millions	6 Months Ended
Jun. 30, 2026	Jun. 30, 2025
Weighted Average Grant Date Fair Value
Taxes paid for restricted unit withholdings	$ 3.7	$ 4.4
RSU and PSU
Weighted Average Grant Date Fair Value
Taxes paid for restricted unit withholdings	$ 3.7
Restricted stock unit
Shares of RSU and PSU
Balance at the beginning of the period (in shares)	4,573,078
Vested (in shares)	(942,900)
Cancelled (in shares)	(882,087)
Nonvested at the end of the period (in shares)	2,748,091
Weighted Average Grant Date Fair Value
Balance at the beginning of the period (in dollars per share)	$ 4.73
Vested (in dollars per share)	5.82
Cancelled (in dollars per share)	5.95
Nonvested at the end of the period (in dollars per share)	$ 3.96
Total nonvested at March 31, 2026	2,748,091
Performance stock unit
Shares of RSU and PSU
Balance at the beginning of the period (in shares)	324,969
Granted (in shares)	3,448,938
Vested (in shares)	(119,307)
Cancelled (in shares)	(97,339)
Nonvested at the end of the period (in shares)	3,557,261
Weighted Average Grant Date Fair Value
Balance at the beginning of the period (in dollars per share)	$ 3.57
Granted (in dollars per share)	1.24
Vested (in dollars per share)	3.57
Cancelled (in dollars per share)	3.57
Nonvested at the end of the period (in dollars per share)	$ 1.35
Tranche Year 2027 awarded under the 2025 PSU award with grant date fair values to be determined in year 2027	1,213,279
Total nonvested at March 31, 2026	4,770,540
Performance stock unit \| Special Award
Shares of RSU and PSU
Granted (in shares)	3,778,642
Vested (in shares)	(2,005,981)
Cancelled (in shares)	(1,772,661)
Weighted Average Grant Date Fair Value
Granted (in dollars per share)	$ 1.22
Vested (in dollars per share)	1.22
Cancelled (in dollars per share)	$ 1.22
2025 Performance share award \| Tranche Year 2027
Weighted Average Grant Date Fair Value
PSUs vesting as a percentage of performance target	100.00%
2026 Performance share award \| Cumulative Adjusted EBITDA Target
Weighted Average Grant Date Fair Value
Percentage of performance target	185.00%
2026 Performance share award \| Cumulative Adjusted Free Cash Flow Target
Weighted Average Grant Date Fair Value
Percentage of performance target	200.00%
2026 Performance share award \| Meeting of strategic initiatives target
Weighted Average Grant Date Fair Value
Percentage of performance target	133.00%

Represents the percentage of PSUs vesting expressed as a percentage of performance target.

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Percentage of performance target.

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Weighted average fair value as of the grant date of equity-based award plans other than stock (unit) option plans that were not exercised or put into effect as a result of the occurrence of cancellation.

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No definition available.

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Number of equity instruments other than options awarded for the next fiscal year; however, the grant date fair values are subject to determination in that particular fiscal year under the share-based compensation arrangement.

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Total number of equity instruments other than options outstanding including the awards for which the grant date fair values are subject to determination in that particular fiscal year under the share based compensation arrangement.

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- Definition

Amount of cash outflow to satisfy grantee's tax withholding obligation for award under share-based payment arrangement.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 230
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 15
-Subparagraph (a)
-Publisher FASB
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The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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- Definition

The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

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

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-Topic 718
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-Section 50
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-Publisher FASB
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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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Per share or unit weighted-average fair value of nonvested award under share-based payment arrangement. Excludes share and unit options.

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- Definition

The net total number of shares (or other type of equity) under an equity-based award plan, other than a stock option plan, that were granted, vested and forfeited during the reporting period.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 718
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-Paragraph 2
-Subparagraph (c)(2)(iii)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480429/718-10-50-2

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- Definition

The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period.

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The weighted average fair value as of grant date pertaining to an equity-based award plan other than a stock (or unit) option plan for which the grantee gained the right during the reporting period, by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash in accordance with the terms of the arrangement.

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