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LONG-TERM DEBT - Schedule of Group's Debt Comprised (Details) € in Millions, £ in Millions, $ in Millions	12 Months Ended
	Dec. 31, 2024 USD ($)	Dec. 31, 2024 EUR (€)	Dec. 31, 2024 GBP (£)	Dec. 31, 2023 USD ($)	Dec. 31, 2023 EUR (€)	Dec. 31, 2023 GBP (£)
Debt Instrument [Line Items]
Outstanding balance	$ 6,788			$ 7,110
Less: unamortized debt issuance costs	(52)			(54)
Total debt	6,736			7,056
Less: current portion of long-term debt	(53)			(51)
Long-term debt	6,683			7,005
USD First Lien Term Loan B due 2028
Debt Instrument [Line Items]
Principal outstanding balance in currency of borrowing Local currency	0			514
Outstanding balance	0			514
EUR First Lien Term Loan B due 2026
Debt Instrument [Line Items]
Principal outstanding balance in currency of borrowing Local currency \| €		€ 0			€ 507
Outstanding balance	0			560
GBP First Lien Term Loan A due 2028
Debt Instrument [Line Items]
Principal outstanding balance in currency of borrowing Local currency \| £			£ 1,034			£ 1,034
Outstanding balance	1,295			1,315
EUR First Lien Term Loan A due 2028
Debt Instrument [Line Items]
Principal outstanding balance in currency of borrowing Local currency \| €		380			380
Outstanding balance	395			419
USD First Lien Term Loan A due 2028
Debt Instrument [Line Items]
Principal outstanding balance in currency of borrowing Local currency	166			166
Outstanding balance	166			166
USD First Lien Term Loan B due 2030
Debt Instrument [Line Items]
Principal outstanding balance in currency of borrowing Local currency	3,875			3,400
Outstanding balance	3,876			3,400
GBP Revolving Credit Facility due 2028
Debt Instrument [Line Items]
Principal outstanding balance in currency of borrowing Local currency \| £			£ 0			£ 578
Outstanding balance	0			736
EUR Senior Secured Notes due 2029
Debt Instrument [Line Items]
Principal outstanding balance in currency of borrowing Local currency \| €		€ 500			€ 0
Outstanding balance	524			0
USD Senior Secured Notes due 2029
Debt Instrument [Line Items]
Principal outstanding balance in currency of borrowing Local currency	525			0
Outstanding balance	$ 532			$ 0