Consolidated Statements of Equity - USD ($) shares in Millions, $ in Millions	Total	Cumulative Effect, Period of Adoption, Adjustment	Shares of Common Stock	Common Stock and Additional Paid-In Capital	Accumulated Deficit	Accumulated Deficit Cumulative Effect, Period of Adoption, Adjustment	Accumulated Other Comprehensive Loss
Beginning balance (in shares) at Jul. 27, 2019			4,250
Beginning balance at Jul. 27, 2019	$ 33,571			$ 40,266	$ (5,903)		$ (792)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Repurchase of common stock (in shares)	(16)
Ending balance (in shares) at Oct. 26, 2019			4,241
Ending balance at Oct. 26, 2019	$ 34,423			40,321	(5,083)		(815)
Beginning balance (in shares) at Jul. 27, 2019			4,250
Beginning balance at Jul. 27, 2019	33,571			40,266	(5,903)		(792)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	5,804				5,804
Other comprehensive income	92						92
Issuance of common stock (in shares)			34
Issuance of common stock	334			334
Repurchase of common stock (in shares)			(34)
Repurchase of common stock	(1,638)			(325)	(1,313)
Shares repurchased for tax withholdings on vesting of restricted stock units (in shares)			(9)
Shares repurchased for tax withholdings on vesting of restricted stock units	(437)			(437)
Cash dividends declared	(2,972)				(2,972)
Share-based compensation	779			779
Ending balance (in shares) at Jan. 25, 2020			4,241
Ending balance at Jan. 25, 2020	35,533			40,617	(4,384)		(700)
Beginning balance (in shares) at Oct. 26, 2019			4,241
Beginning balance at Oct. 26, 2019	34,423			40,321	(5,083)		(815)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	2,878				2,878
Other comprehensive income	115						115
Issuance of common stock (in shares)			23
Issuance of common stock	$ 332			332
Repurchase of common stock (in shares)	(18)		(18)
Repurchase of common stock	$ (870)			(177)	(693)
Shares repurchased for tax withholdings on vesting of restricted stock units (in shares)			(5)
Shares repurchased for tax withholdings on vesting of restricted stock units	(243)			(243)
Cash dividends declared	(1,486)				(1,486)
Share-based compensation	384			384
Ending balance (in shares) at Jan. 25, 2020			4,241
Ending balance at Jan. 25, 2020	35,533			40,617	(4,384)		(700)
Beginning balance (in shares) at Jul. 25, 2020			4,237
Beginning balance at Jul. 25, 2020	$ 37,920	$ (38)		41,202	(2,763)	$ (38)	(519)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Repurchase of common stock (in shares)	(20)
Ending balance (in shares) at Oct. 24, 2020			4,222
Ending balance at Oct. 24, 2020	$ 38,157			41,360	(2,756)		(447)
Beginning balance (in shares) at Jul. 25, 2020			4,237
Beginning balance at Jul. 25, 2020	37,920	$ (38)		41,202	(2,763)	$ (38)	(519)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	4,719				4,719
Other comprehensive income	301						301
Issuance of common stock (in shares)			31
Issuance of common stock	306			306
Repurchase of common stock (in shares)			(39)
Repurchase of common stock	(1,601)			(375)	(1,226)
Shares repurchased for tax withholdings on vesting of restricted stock units (in shares)			(8)
Shares repurchased for tax withholdings on vesting of restricted stock units	(317)			(317)
Cash dividends declared	(3,043)				(3,043)
Share-based compensation	874			874
Ending balance (in shares) at Jan. 23, 2021			4,221
Ending balance at Jan. 23, 2021	39,121			41,690	(2,351)		(218)
Beginning balance (in shares) at Oct. 24, 2020			4,222
Beginning balance at Oct. 24, 2020	38,157			41,360	(2,756)		(447)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	2,545				2,545
Other comprehensive income	229						229
Issuance of common stock (in shares)			24
Issuance of common stock	$ 305			305
Repurchase of common stock (in shares)	(19)		(19)
Repurchase of common stock	$ (801)			(183)	(618)
Shares repurchased for tax withholdings on vesting of restricted stock units (in shares)			(6)
Shares repurchased for tax withholdings on vesting of restricted stock units	(228)			(228)
Cash dividends declared	(1,522)				(1,522)
Share-based compensation	436			436
Ending balance (in shares) at Jan. 23, 2021			4,221
Ending balance at Jan. 23, 2021	$ 39,121			$ 41,690	$ (2,351)		$ (218)