Consolidated Statements of Equity - USD ($) shares in Millions, $ in Millions	Total	Shares of Common Stock	Common Stock and Additional Paid-In Capital	Retained Earnings (Accumulated Deficit)	Accumulated Other Comprehensive Income (Loss)	Cumulative Effect, Period of Adoption, Adjustment	Cumulative Effect, Period of Adoption, Adjustment Retained Earnings (Accumulated Deficit)	Cumulative Effect, Period of Adoption, Adjustment Accumulated Other Comprehensive Income (Loss)
Beginning balance (in shares) at Jul. 29, 2017		4,983
Balance, beginning of period at Jul. 29, 2017	$ 66,137		$ 45,253	$ 20,838	$ 46	$ 9	$ (36)	$ 45
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	110			110
Other comprehensive income (loss)	(940)				(940)
Issuance of common stock (in shares)		83
Issuance of common stock	$ 623		623
Repurchase of common stock (in shares)	(432)	(432)
Repurchase of common stock	$ (17,661)		(3,950)	(13,711)
Shares repurchased for tax withholdings on vesting of restricted stock units (in shares)		(20)
Shares repurchased for tax withholdings on vesting of restricted stock units	(703)		(703)
Cash dividends declared	(5,968)			(5,968)
Share-based compensation	1,576		1,576
Purchase acquisitions and other	21		21
Ending Balance (in shares) at Jul. 28, 2018		4,614
Balance, end of period at Jul. 28, 2018	43,204		42,820	1,233	(849)	$ 3,729	$ 3,897	$ (168)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	11,621			11,621
Other comprehensive income (loss)	225				225
Issuance of common stock (in shares)		71
Issuance of common stock	$ 640		640
Repurchase of common stock (in shares)	(418)	(418)
Repurchase of common stock	$ (20,577)		(3,902)	(16,675)
Shares repurchased for tax withholdings on vesting of restricted stock units (in shares)		(17)
Shares repurchased for tax withholdings on vesting of restricted stock units	(862)		(862)
Cash dividends declared	(5,979)			(5,979)
Share-based compensation	1,570		1,570
Ending Balance (in shares) at Jul. 27, 2019		4,250
Balance, end of period at Jul. 27, 2019	33,571		40,266	(5,903)	(792)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	11,214			11,214
Other comprehensive income (loss)	273				273
Issuance of common stock (in shares)		61
Issuance of common stock	$ 655		655
Repurchase of common stock (in shares)	(59)	(59)
Repurchase of common stock	$ (2,619)		(561)	(2,058)
Shares repurchased for tax withholdings on vesting of restricted stock units (in shares)		(15)
Shares repurchased for tax withholdings on vesting of restricted stock units	(727)		(727)
Cash dividends declared	(6,016)			(6,016)
Share-based compensation	1,569		1,569
Ending Balance (in shares) at Jul. 25, 2020		4,237
Balance, end of period at Jul. 25, 2020	$ 37,920		$ 41,202	$ (2,763)	$ (519)