Selected quarterly financial data (unaudited) (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended								12 Months Ended
	Dec. 31, 2023	Oct. 01, 2023	Jul. 02, 2023	Apr. 02, 2023	Jan. 01, 2023	Oct. 02, 2022	Jul. 03, 2022	Apr. 03, 2022	Dec. 31, 2023	Jan. 01, 2023	Jan. 02, 2022	Aug. 23, 2023
Segment Reporting Information [Line Items]
Sales to customers	$ 21,395	$ 21,351	$ 21,519	$ 20,894	$ 19,939	$ 19,996	$ 20,215	$ 19,840	$ 85,159	$ 79,990	$ 78,740
Gross profit	14,597	14,745	15,057	14,207	13,855	13,824	13,893	13,822	58,606	55,394	55,338
Earnings before provision for taxes on income	4,826	5,217	6,306	(1,287)	3,840	5,172	5,144	5,203	15,062	19,359	19,178
Net earnings from continuing operations	4,132	4,309	5,376	(491)	3,227	4,310	4,262	4,571	13,326	16,370	17,801
Net earnings from discontinued operations	(83)	21,719	(232)	423	293	148	552	578	21,827	1,571	3,077
Net earnings	$ 4,049	$ 26,028	$ 5,144	$ (68)	$ 3,520	$ 4,458	$ 4,814	$ 5,149	$ 35,153	$ 17,941	$ 20,878
Basic net earnings per share from continuing operations (in dollars per share)	$ 1.71	$ 1.71	$ 2.07	$ (0.19)	$ 1.24	$ 1.64	$ 1.62	$ 1.74	$ 5.26	$ 6.23	$ 6.76
Basic net earnings per share from discontinued operations (in dollars per share)	(0.03)	8.61	(0.09)	0.16	0.11	0.06	0.21	0.22	8.62	0.60	1.17
Basic net earnings per share (in dollars per share)	1.68	10.32	1.98	(0.03)	1.35	1.70	1.83	1.96	13.88	6.83	7.93
Diluted net earnings per share from continuing operations (in dollars per share)	1.70	1.69	2.05	(0.19)	1.22	1.62	1.60	1.71	5.20	6.14	6.66
Diluted net earnings per share from discontinuing operations (in dollars per share)	(0.03)	8.52	(0.09)	0.16	0.11	0.06	0.20	0.22	8.52	0.59	1.15
Diluted net earnings per share (in dollars per share)	$ 1.67	$ 10.21	$ 1.96	$ (0.03)	$ 1.33	$ 1.68	$ 1.80	$ 1.93	$ 13.72	$ 6.73	$ 7.81
Equity securities, FV-NI, gain (loss)		$ 600							$ (400)
MedTech
Segment Reporting Information [Line Items]
Sales to customers	$ 7,673	7,458	$ 7,788	$ 7,481	$ 6,776	$ 6,782	$ 6,898	$ 6,971	30,400	$ 27,427	$ 27,060
Innovative Medicine
Segment Reporting Information [Line Items]
Sales to customers	13,722	13,893	$ 13,731	$ 13,413	13,163	$ 13,214	$ 13,317	12,869	54,759	52,563	51,680
Marketable securities, realized gain (loss)	$ 400	$ 400							(400)	(700)	500
bermekimab | In Process Research and Development
Segment Reporting Information [Line Items]
Impairment of intangible assets, excluding goodwill								$ 600		800
Operating Segments
Segment Reporting Information [Line Items]
Sales to customers									85,159	79,990	78,740
Earnings before provision for taxes on income									22,915	20,094	21,958
Operating Segments | MedTech
Segment Reporting Information [Line Items]
Earnings before provision for taxes on income									4,669	4,447	4,208
Operating Segments | Innovative Medicine
Segment Reporting Information [Line Items]
Earnings before provision for taxes on income									18,246	15,647	$ 17,750
Supplies expense					$ 800				$ 700	$ 1,500
Consumer Health Business
Segment Reporting Information [Line Items]
Noncash gain on exchange offer												$ 21,000