SEGMENTS AND DISAGGREGATION OF REVENUE - Schedule of Reconciliation of Reportable Segment Adjusted EBITDA to Income (Loss) Before Taxes (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Depreciation and amortization	$ (1,097)	$ (1,285)	$ (1,075)
Share-based compensation expense	(202)	(190)	(181)
Other (expense) income, net	(434)	(157)	5
Interest expense, net	(419)	(385)	(212)
Impairment loss	0	(725)	0
Income (loss) before income taxes	16	(1,091)	(295)
Operating Segments
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Reportable segment adjusted EBITDA	2,572	2,062	1,414
Segment Reporting, Reconciling Item, Excluding Corporate Nonsegment
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Unallocated corporate overhead	(215)	(187)	(126)
Depreciation and amortization	(1,097)	(1,285)	(1,075)
Share-based compensation expense	(202)	(190)	(181)
Legal settlements	0	0	44
Transaction fees and associated costs	(54)	(92)	(43)
Transaction fees and associated costs	(135)	(132)	(121)
Other (expense) income, net	(434)	(157)	5
Interest expense, net	(419)	(385)	(212)
Impairment loss	0	(725)	0
UKI
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Reportable segment adjusted EBITDA	1,117	911	776
UKI \| Operating Segments
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Reportable segment adjusted EBITDA	1,117	911	776
U.S.
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Reportable segment adjusted EBITDA	507	232	(175)
U.S. \| Operating Segments
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Reportable segment adjusted EBITDA	507	232	(175)
International
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Reportable segment adjusted EBITDA	653	562	328
International \| Operating Segments
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Reportable segment adjusted EBITDA	653	562	328
Australia
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Reportable segment adjusted EBITDA	295	357	485
Australia \| Operating Segments
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Reportable segment adjusted EBITDA	$ 295	$ 357	$ 485

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Amount of income (loss) from continuing operations, including income (loss) from equity method investments, before deduction of income tax expense (benefit), and income (loss) attributable to noncontrolling interest.

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