Capital and treasury stock - Changes in Treasury Stock (Details) - USD ($) shares in Thousands, $ in Millions	12 Months Ended
	Dec. 29, 2024	Dec. 31, 2023	Jan. 01, 2023
Changes in Treasury Stock Shares Outstanding [Roll Forward]
Treasury Stock, beginning balance (shares)	712,765	506,246	490,878
Employee compensation and stock option plans (shares)	(15,027)	(15,521)	(20,007)
Treasury Stock, ending balance (shares)	712,921	712,765	506,246
Changes in treasury stock
Treasury Stock, Balance	$ 75,662	$ 41,694	$ 39,099
Employee compensation and stock option plans	(2,389)	(2,529)	(3,440)
Repurchase of common stock	2,407	5,054	6,035
Treasury Stock, Ending Balance	$ 75,680	$ 75,662	$ 41,694
Treasury Stock Amount
Changes in Treasury Stock Shares Outstanding [Roll Forward]
Treasury Stock, beginning balance (shares)	190,955
Repurchase of common stock (shares)	15,183	31,085	35,375
Treasury Stock, ending balance (shares)		190,955
Changes in treasury stock
Treasury Stock, Balance	$ 31,418
Repurchase of common stock	2,407	$ 5,054	$ 6,035
Repurchase of common stock	$ 2,407	5,079
Treasury Stock, Ending Balance		$ 31,418