Financing arrangements - Debt Issuances and Acquisition-Related Financing (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Oct. 31, 2023	Mar. 31, 2023	Dec. 31, 2022
Notes
Debt Instrument [Line Items]
Principal Amount	$ 0			$ 24,000	$ 7,000
Notes \| 3.00% notes due 2029 (3.00% 2029 Notes)
Debt Instrument [Line Items]
Principal Amount					$ 750
Interest rate, stated percentage	3.00%				3.00%
Notes \| 4.05% notes due 2029 (4.05% 2029 Notes)
Debt Instrument [Line Items]
Principal Amount					$ 1,250
Interest rate, stated percentage	4.05%				4.05%
Notes \| 3.35% notes due 2032 (3.35% 2032 Notes)
Debt Instrument [Line Items]
Principal Amount					$ 1,000
Interest rate, stated percentage	3.35%				3.35%
Notes \| 4.20% notes due 2033 (4.20% 2033 Notes)
Debt Instrument [Line Items]
Principal Amount					$ 750
Interest rate, stated percentage	4.20%				4.20%
Notes \| 4.20% notes due 2052 (4.20% 2052 Notes)
Debt Instrument [Line Items]
Principal Amount					$ 1,000
Interest rate, stated percentage	4.20%	4.20%			4.20%
Notes \| 4.875% notes due 2053 (4.875% 2053 Notes)
Debt Instrument [Line Items]
Principal Amount					$ 1,000
Interest rate, stated percentage	4.875%				4.875%
Notes \| 4.40% notes due 2062 (4.40% 2062 Notes)
Debt Instrument [Line Items]
Principal Amount					$ 1,250
Interest rate, stated percentage	4.40%	4.40%			4.40%
Variable Rate Component Three \| Term Loan Credit Agreement
Debt Instrument [Line Items]
Basis spread on variable rate	1.225%
Horizon Therapeutics
Debt Instrument [Line Items]
Term loan credit agreement, total amount					$ 4,000
Term loan credit agreement, total borrowed			$ 4,000
Repayments of term loan credit agreement	$ 2,200
Term loan, outstanding	$ 1,800