Investments - Available-for-Sale Investments With Gross Unrealized Losses (Details) - USD ($) $ in Millions	Jan. 25, 2025	Jul. 27, 2024
Debt Securities, Available-for-sale [Line Items]
UNREALIZED LOSSES LESS THAN 12 MONTHS, Fair Value	$ 1,750	$ 1,228
UNREALIZED LOSSES LESS THAN 12 MONTHS, Gross Unrealized Losses	(19)	(4)
UNREALIZED LOSSES 12 MONTHS OR GREATER, Fair Value	3,356	5,764
UNREALIZED LOSSES 12 MONTHS OR GREATER, Gross Unrealized Losses	(187)	(320)
TOTAL, Fair Value	5,106	6,992
TOTAL, Gross Unrealized Losses	(206)	(324)
U.S. government securities
Debt Securities, Available-for-sale [Line Items]
UNREALIZED LOSSES LESS THAN 12 MONTHS, Fair Value	1,431	598
UNREALIZED LOSSES LESS THAN 12 MONTHS, Gross Unrealized Losses	(17)	(2)
UNREALIZED LOSSES 12 MONTHS OR GREATER, Fair Value	387	1,399
UNREALIZED LOSSES 12 MONTHS OR GREATER, Gross Unrealized Losses	(12)	(26)
TOTAL, Fair Value	1,818	1,997
TOTAL, Gross Unrealized Losses	(29)	(28)
U.S. government agency securities
Debt Securities, Available-for-sale [Line Items]
UNREALIZED LOSSES LESS THAN 12 MONTHS, Fair Value	30	89
UNREALIZED LOSSES LESS THAN 12 MONTHS, Gross Unrealized Losses	0	0
UNREALIZED LOSSES 12 MONTHS OR GREATER, Fair Value	48	109
UNREALIZED LOSSES 12 MONTHS OR GREATER, Gross Unrealized Losses	(1)	(2)
TOTAL, Fair Value	78	198
TOTAL, Gross Unrealized Losses	(1)	(2)
Non-U.S. government and agency securities
Debt Securities, Available-for-sale [Line Items]
UNREALIZED LOSSES LESS THAN 12 MONTHS, Fair Value		17
UNREALIZED LOSSES LESS THAN 12 MONTHS, Gross Unrealized Losses		0
UNREALIZED LOSSES 12 MONTHS OR GREATER, Fair Value		0
UNREALIZED LOSSES 12 MONTHS OR GREATER, Gross Unrealized Losses		0
TOTAL, Fair Value		17
TOTAL, Gross Unrealized Losses		0
Corporate debt securities
Debt Securities, Available-for-sale [Line Items]
UNREALIZED LOSSES LESS THAN 12 MONTHS, Fair Value	281	276
UNREALIZED LOSSES LESS THAN 12 MONTHS, Gross Unrealized Losses	(2)	(1)
UNREALIZED LOSSES 12 MONTHS OR GREATER, Fair Value	2,193	2,818
UNREALIZED LOSSES 12 MONTHS OR GREATER, Gross Unrealized Losses	(63)	(115)
TOTAL, Fair Value	2,474	3,094
TOTAL, Gross Unrealized Losses	(65)	(116)
U.S. agency mortgage-backed securities
Debt Securities, Available-for-sale [Line Items]
UNREALIZED LOSSES LESS THAN 12 MONTHS, Fair Value	8	238
UNREALIZED LOSSES LESS THAN 12 MONTHS, Gross Unrealized Losses	0	(1)
UNREALIZED LOSSES 12 MONTHS OR GREATER, Fair Value	728	1,438
UNREALIZED LOSSES 12 MONTHS OR GREATER, Gross Unrealized Losses	(111)	(177)
TOTAL, Fair Value	736	1,676
TOTAL, Gross Unrealized Losses	$ (111)	(178)
Commercial paper
Debt Securities, Available-for-sale [Line Items]
UNREALIZED LOSSES LESS THAN 12 MONTHS, Fair Value		10
UNREALIZED LOSSES LESS THAN 12 MONTHS, Gross Unrealized Losses		0
UNREALIZED LOSSES 12 MONTHS OR GREATER, Fair Value		0
UNREALIZED LOSSES 12 MONTHS OR GREATER, Gross Unrealized Losses		0
TOTAL, Fair Value		10
TOTAL, Gross Unrealized Losses		$ 0