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]
Net income	2,926				2,926
Other comprehensive income (loss)	(23)						(23)
Issuance of common stock (in shares)			11
Issuance of common stock	$ 2			2
Repurchase of common stock (in shares)	(16)		(16)
Repurchase of common stock	$ (768)			(148)	(620)
Shares repurchased for tax withholdings on vesting of restricted stock units (in shares)			(4)
Shares repurchased for tax withholdings on vesting of restricted stock units	(194)			(194)
Cash dividends declared	(1,486)				(1,486)
Share-based compensation	395			395
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. 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	2,174				2,174
Other comprehensive income (loss)	72						72
Issuance of common stock (in shares)			7
Issuance of common stock	$ 1			1
Repurchase of common stock (in shares)	(20)		(20)
Repurchase of common stock	$ (800)			(192)	(608)
Shares repurchased for tax withholdings on vesting of restricted stock units (in shares)			(2)
Shares repurchased for tax withholdings on vesting of restricted stock units	(89)			(89)
Cash dividends declared	(1,521)				(1,521)
Share-based compensation	438			438
Ending balance (in shares) at Oct. 24, 2020			4,222
Ending balance at Oct. 24, 2020	$ 38,157			$ 41,360	$ (2,756)		$ (447)