Segments of Business and Geographic Areas - Schedule of Segment Reporting Information (Details) - USD ($) $ in Millions	12 Months Ended
Jan. 03, 2021	Dec. 29, 2019	Dec. 30, 2018
Segment Reporting Information [Line Items]
Earnings before provision for taxes on income	$ 16,497	$ 17,328	$ 17,999
Identifiable Assets	174,894	157,728
Additions to Property, Plant & Equipment	3,347	3,498	3,670
Depreciation and Amortization	7,231	7,009	6,929
Sales to Customers	$ 82,584	$ 82,059	$ 81,581
Wholesaler 2 \| Sales Revenue, Net
Segment Reporting Information [Line Items]
Concentration risk (as a percent)	12.00%	12.00%	11.00%
United States
Segment Reporting Information [Line Items]
Sales to Customers	$ 43,133	$ 42,097	$ 41,884
Non-US
Segment Reporting Information [Line Items]
Sales to Customers	39,451	39,962	39,697
Consumer
Segment Reporting Information [Line Items]
Sales to Customers	14,053	13,898	13,853
Consumer \| United States
Segment Reporting Information [Line Items]
Sales to Customers	6,362	5,839	5,761
Consumer \| Non-US
Segment Reporting Information [Line Items]
Sales to Customers	7,691	8,059	8,092
Pharmaceutical
Segment Reporting Information [Line Items]
Sales to Customers	45,572	42,198	40,734
Pharmaceutical \| United States
Segment Reporting Information [Line Items]
Sales to Customers	25,735	23,874	23,286
Pharmaceutical \| Non-US
Segment Reporting Information [Line Items]
Sales to Customers	19,837	18,324	17,448
Medical Devices
Segment Reporting Information [Line Items]
Sales to Customers	22,959	25,963	26,994
Medical Devices \| United States
Segment Reporting Information [Line Items]
Sales to Customers	11,036	12,384	12,837
Medical Devices \| Non-US
Segment Reporting Information [Line Items]
Sales to Customers	11,923	13,579	14,157
Segments Total
Segment Reporting Information [Line Items]
Identifiable Assets	143,091	132,372
Additions to Property, Plant & Equipment	3,091	3,190	3,293
Depreciation and Amortization	6,931	6,689	6,593
Corporate, Non-Segment
Segment Reporting Information [Line Items]
Less: Expense not allocated to segments	945	835	1,286
Corporate, Non-Segment \| General Corporate
Segment Reporting Information [Line Items]
Identifiable Assets	31,803	25,356
Additions to Property, Plant & Equipment	256	308	377
Depreciation and Amortization	300	320	336
Operating Segments
Segment Reporting Information [Line Items]
Earnings before provision for taxes on income	17,442	18,163	19,285
Sales to Customers	82,584	82,059	81,581
Operating Segments \| United States
Segment Reporting Information [Line Items]
Sales to Customers	43,133	42,097	41,884
Operating Segments \| Consumer
Segment Reporting Information [Line Items]
Earnings before provision for taxes on income	(1,064)	2,061	2,320
Identifiable Assets	27,355	26,618
Additions to Property, Plant & Equipment	248	328	438
Depreciation and Amortization	785	765	688
Operating Segments \| Pharmaceutical
Segment Reporting Information [Line Items]
Earnings before provision for taxes on income	15,462	8,816	12,568
Identifiable Assets	66,158	56,292
Additions to Property, Plant & Equipment	863	950	1,012
Depreciation and Amortization	4,006	3,910	3,802
Operating Segments \| Medical Devices
Segment Reporting Information [Line Items]
Earnings before provision for taxes on income	3,044	7,286	4,397
Identifiable Assets	49,578	49,462
Additions to Property, Plant & Equipment	1,980	1,912	1,843
Depreciation and Amortization	2,140	2,014	2,103
Immunology \| Pharmaceutical
Segment Reporting Information [Line Items]
Sales to Customers	15,055	13,950	13,120
Immunology \| Pharmaceutical \| United States
Segment Reporting Information [Line Items]
Sales to Customers	10,175	9,641	9,073
Immunology \| Pharmaceutical \| Non-US
Segment Reporting Information [Line Items]
Sales to Customers	$ 4,880	$ 4,309	$ 4,047

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Sum of the carrying amounts as of the balance sheet date of all assets that are recognized. Assets are probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

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The aggregate expense recognized in the current period that allocates the cost of tangible assets, intangible assets, or depleting assets to periods that benefit from use of the assets.

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Amount of acquisition of long-lived, physical assets used in the normal conduct of business and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

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