Legal proceedings - Narrative (Details) $ in Millions			1 Months Ended					3 Months Ended
	Sep. 20, 2024 USD ($)	May 01, 2024 USD ($)	Jun. 30, 2021 USD ($)	Jun. 30, 2020 USD ($)	Jan. 31, 2020 USD ($)	Oct. 31, 2019 USD ($)	Jul. 31, 2018 USD ($)	Dec. 29, 2024 USD ($) claimant	Sep. 30, 2021 cases	Jul. 04, 2021 USD ($)	May 31, 2021 cases claimant
Talc
Legal Proceeding (Textuals)
Product liability contingency, number of claimants | claimant								62,830
Opioid
Legal Proceeding (Textuals)
Product liability contingency, number of claimants | claimant								3,500
Amount reserved for settlement										$ 5,000.0
Loss contingency accrual, payment percentage										70.00%
Physiomesh
Legal Proceeding (Textuals)
Product liability contingency, number of claimants | claimant								130
Judicial Ruling
Legal Proceeding (Textuals)
Damages awarded					$ 6.8	$ 8,000.0
Pending Litigation | Physiomesh
Legal Proceeding (Textuals)
Product liability contingency, number of claimants | claimant											4,300
Number of pending claims | cases											3,600
Number of claims within settlement agreement | cases									3,729
DePuy ASR U.S. | Settled Litigation
Legal Proceeding (Textuals)
Number of patients in settlement | claimant								10,000
Ingham vs. Johnson & Johnson
Legal Proceeding (Textuals)
Damages awarded				$ 2,100.0			$ 4,700.0
Loss contingency, damages paid, value			$ 2,500.0
Talc
Legal Proceeding (Textuals)
Loss contingency, payment period		25 years
Solicitation period		3 months
Litigation contingency		$ 6,475.0
Damages sought, nominal value		$ 8,000.0
Bankruptcy loss contingency, discount rate		4.40%
Total claims against company, percent		99.75%
Increase in damages sought	$ 1,750.0
Incremental charges								$ 5,000.0
Accrual, nominal value								13,500.0
Amount reserved for settlement								$ 11,600.0
Mesothelioma and State Claims
Legal Proceeding (Textuals)
Claims settled, percent		95.00%