Derivative instruments and hedging activities - Summary of Pre-tax (Gains) Losses From Derivatives Not Designated in as Hedging Instruments (Detail) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2026	Sep. 30, 2025	Sep. 30, 2026	Sep. 30, 2025	May 31, 2025
Designated as hedging instruments \| 5.25% Senior notes due 2032 \| Cross currency interest rate swap
Derivative [Line Items]
Debt instrument face amount	$ 750		$ 750
Weighted average interest rate	5.25%		5.25%
Designated as hedging instruments \| 5.75% Senior notes due 2030 \| Cross currency interest rate swap
Derivative [Line Items]
Debt instrument face amount					$ 500
Weighted average interest rate					5.75%
Income Statement Location [Axis]: us-gaap:NonoperatingIncomeExpense \| Line items in which effects of hedges are recorded
Derivative [Line Items]
Gain (loss) from derivatives	$ 414	$ 237	$ 854	$ 714
Income Statement Location [Axis]: us-gaap:NonoperatingIncomeExpense \| Option and forward contracts
Derivative [Line Items]
Gain (loss) from derivatives	30	4	10	8
Income Statement Location [Axis]: us-gaap:NonoperatingIncomeExpense \| Option and forward contracts economic hedge
Derivative [Line Items]
Gain (loss) from derivatives	0	0	0	0
Income Statement Location [Axis]: us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax \| Line items in which effects of hedges are recorded
Derivative [Line Items]
Gain (loss) from derivatives	(4,395)	(4,480)	(12,519)	(12,547)
Income Statement Location [Axis]: us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax \| Option and forward contracts
Derivative [Line Items]
Gain (loss) from derivatives	0	0	0	0
Income Statement Location [Axis]: us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax \| Option and forward contracts economic hedge
Derivative [Line Items]
Gain (loss) from derivatives	$ (24)	$ (9)	$ (27)	$ 51