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Long-Term Debt - Schedule of Group's debt comprised (Detail) € in Millions, £ in Millions, $ in Millions	3 Months Ended
	Mar. 31, 2024 USD ($)	Mar. 31, 2024 EUR (€)	Mar. 31, 2024 GBP (£)	Dec. 31, 2023 USD ($)	Dec. 31, 2023 EUR (€)	Dec. 31, 2023 GBP (£)
Debt Instrument [Line Items]
Long-Term Debt, Gross	$ 6,888			$ 7,110
Less: unamortized debt issuance costs	(52)			(54)
Total debt	6,836			7,056
Current portion	(46)			(51)
Total long-term debt	6,790			7,005
USD First Lien Term Loan B Due 2028 [Member]
Debt Instrument [Line Items]
Long-Term Debt, Gross	$ 0			514
Debt Instrument, Maturity Date, Description	2028
USD First Lien Term Loan B Due 2028 [Member] \| Domestic Line of Credit [Member]
Debt Instrument [Line Items]
Long-Term Debt, Gross	$ 0			514
EUR First Lien Term Loan B Due 2026 [Member]
Debt Instrument [Line Items]
Long-Term Debt, Gross	$ 548			560
Debt Instrument, Maturity Date, Description	2026
EUR First Lien Term Loan B Due 2026 [Member] \| Domestic Line of Credit [Member]
Debt Instrument [Line Items]
Long-Term Debt, Gross \| €		€ 507			€ 507
GBP First Lien Term Loan A Due 2028 [Member]
Debt Instrument [Line Items]
Long-Term Debt, Gross	$ 1,307			1,315
Debt Instrument, Maturity Date, Description	2028
GBP First Lien Term Loan A Due 2028 [Member] \| Domestic Line of Credit [Member]
Debt Instrument [Line Items]
Long-Term Debt, Gross \| £			£ 1,034			£ 1,034
EUR First Lien Term Loan A Due 2028 [Member]
Debt Instrument [Line Items]
Long-Term Debt, Gross	$ 411			419
Debt Instrument, Maturity Date, Description	2028
EUR First Lien Term Loan A Due 2028 [Member] \| Domestic Line of Credit [Member]
Debt Instrument [Line Items]
Long-Term Debt, Gross \| €		€ 380			€ 380
USD First Lien Term Loan A Due 2028 [Member]
Debt Instrument [Line Items]
Long-Term Debt, Gross	$ 166			166
Debt Instrument, Maturity Date, Description	2028
USD First Lien Term Loan A Due 2028 [Member] \| Domestic Line of Credit [Member]
Debt Instrument [Line Items]
Long-Term Debt, Gross	$ 166			166
USD First Lien Term Loan B Due 2030 [Member]
Debt Instrument [Line Items]
Long-Term Debt, Gross	$ 3,908			3,400
Debt Instrument, Maturity Date, Description	2030
USD First Lien Term Loan B Due 2030 [Member] \| Domestic Line of Credit [Member]
Debt Instrument [Line Items]
Long-Term Debt, Gross	$ 3,905			3,400
GBP Revolving Credit Facility Due 2028 [Member]
Debt Instrument [Line Items]
Long-Term Debt, Gross	$ 548			$ 736
Debt Instrument, Maturity Date, Description	2028
GBP Revolving Credit Facility Due 2028 [Member] \| Domestic Line of Credit [Member]
Debt Instrument [Line Items]
Long-Term Debt, Gross \| £			£ 433			£ 578