Capital and treasury stock - Changes in Treasury Stock (Details) - USD ($) shares in Thousands, $ in Millions	12 Months Ended
Dec. 31, 2023	Jan. 01, 2023	Jan. 02, 2022
Changes in Treasury Stock Shares Outstanding [Roll Forward]
Treasury Stock, beginning balance (shares)	506,246	490,878	487,331
Employee compensation and stock option plans (shares)	(15,521)	(20,007)	(17,399)
Treasury Stock, ending balance (shares)	712,765	506,246	490,878
Changes in treasury stock
Treasury Stock, Balance	$ 41,694	$ 39,099	$ 38,490
Employee compensation and stock option plans	(2,529)	(3,440)	(2,847)
Repurchase of common stock	5,054	6,035	3,456
Treasury Stock, Ending Balance	$ 75,662	$ 41,694	$ 39,099
Treasury Stock Amount
Changes in Treasury Stock Shares Outstanding [Roll Forward]
Repurchase of common stock (shares)	31,085	35,375	20,946
Treasury Stock, ending balance (shares)	190,955
Changes in treasury stock
Repurchase of common stock	$ 5,054	$ 6,035	$ 3,456
Repurchase of common stock	5,079
Treasury Stock, Ending Balance	$ 31,418

Changes in treasury stock.

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Changes in Treasury Stock Shares Outstanding [Roll Forward]

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Treasury Stock, Value, Acquired, Cost Method, Net Of Tax

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Number of shares of stock issued attributable to transactions classified as other.

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Value of shares of stock issued attributable to transactions classified as other.

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Number of previously issued common shares repurchased by the issuing entity and held in treasury.

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Number of shares that have been repurchased during the period and are being held in treasury.

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The amount allocated to treasury stock. Treasury stock is common and preferred shares of an entity that were issued, repurchased by the entity, and are held in its treasury.

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Equity impact of the cost of common and preferred stock that were repurchased during the period. Recorded using the cost method.

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