Derivative instruments - Summary of Income and Expense Line Items (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Derivative Instruments, Gain (Loss) [Line Items]
Product sales	$ 7,447	$ 6,105
Other (expense) income, net	(235)	2,064
Interest expense, net	(824)	(543)
Interest rate swap agreements
Derivative Instruments, Gain (Loss) [Line Items]
Gains (losses) on fair value hedging relationships, Hedged items	49	(88)
Gains (losses) on fair value hedging relationships, Derivatives designated as hedging instruments	(28)	114
Reclassification out of Accumulated Other Comprehensive Income | Cash flow hedges | Cross-currency swap contracts
Derivative Instruments, Gain (Loss) [Line Items]
Other (expense) income, net	(31)	(22)
Product sales
Derivative Instruments, Gain (Loss) [Line Items]
Product sales	7,118	5,846
Product sales | Reclassification out of Accumulated Other Comprehensive Income | Cash flow hedges | Foreign currency forward contracts
Derivative Instruments, Gain (Loss) [Line Items]
Product sales	$ 51	$ 52