Net Income per Share - Calculation of Basic and Diluted Net Income per Share (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	3 Months Ended		9 Months Ended
	May 01, 2021	Apr. 25, 2020	May 01, 2021	Apr. 25, 2020
Earnings Per Share [Abstract]
Net income	$ 2,863	$ 2,774	$ 7,582	$ 8,578
Weighted-average shares—basic (in shares)	4,219	4,230	4,224	4,239
Effect of dilutive potential common shares (in shares)	19	13	13	19
Weighted-average shares—diluted (in shares)	4,238	4,243	4,237	4,258
Net income per share—basic (in dollars per share)	$ 0.68	$ 0.66	$ 1.79	$ 2.02
Net income per share—diluted (in dollars per share)	$ 0.68	$ 0.65	$ 1.79	$ 2.01
Antidilutive employee share-based awards, excluded (in shares)	15	14	55	42