Borrowings - Additional Information (Detail) £ in Millions	3 Months Ended
	Mar. 31, 2025 USD ($)	Mar. 31, 2025 GBP (£)	Dec. 31, 2024 USD ($)
Debt Instrument [Line Items]
Line of credit facility, covenant terms	The 2025 Credit Facility permits the Company to request up to an additional $1.0 billion of borrowing capacity, subject to lender credit approval, which could increase the overall size of the 2025 Credit Facility to an aggregate principal amount of up to $6.4 billion. Interest on outstanding borrowings accrues at an applicable benchmark rate for the denominated currency of the loan, plus a spread. The 2025 Credit Facility requires the Company not to exceed a maximum leverage ratio (ratio of net debt to earnings before interest, taxes, depreciation and amortization, where net debt equals total debt less unrestricted cash) of 3 to 1
Borrowings	$ 12,349,000,000		$ 12,314,000,000
Fair Value	11,911,000,000		$ 11,700,000,000
Commercial Paper [Member]
Debt Instrument [Line Items]
Maximum amount available under facility	5,000,000,000
Amount outstanding under credit facility	0
2025 Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Unsecured revolving credit facility	5,400,000,000
Additional amount available, subject to lender credit approval	1,000,000,000
Maximum amount available under facility	$ 6,400,000,000
Line of credit facility, interest rate description	Interest on outstanding borrowings accrues at an applicable benchmark rate for the denominated currency of the loan, plus a spread.
Amount outstanding under credit facility	$ 0
Line of credit facility, covenant compliance	less than 1 to 1
Maximum leverage ratio required by credit facility	3 to 1
2025 Subsidiary Credit Facility [Member] | Subsidiaries [Member]
Debt Instrument [Line Items]
Maximum amount available under facility	$ 32,000,000	£ 25
Amount outstanding under credit facility	$ 0