Fair Value - Assets and Liabilities Measured at Fair Value on Recurring Basis (Details) - USD ($) $ in Millions	Jan. 25, 2025	Jul. 27, 2024
Assets:
Available-for-sale debt investments:	$ 7,958	$ 9,865
Marketable equity securities	339	481
Derivative assets	105	64
Total	14,871	15,564
Liabilities:
Derivative liabilities	70	74
Total	70	74
Money market funds
Assets:
Other current assets:	750	750
Other assets:	188	563
U.S. government securities
Assets:
Available-for-sale debt investments:	2,148	2,353
U.S. government agency securities
Assets:
Available-for-sale debt investments:	111	221
Non-U.S. government and agency securities
Assets:
Available-for-sale debt investments:	364	371
Corporate debt securities
Assets:
Available-for-sale debt investments:	3,204	3,677
U.S. agency mortgage-backed securities
Assets:
Available-for-sale debt investments:	736	1,781
Commercial paper
Assets:
Available-for-sale debt investments:	732	1,023
Certificates of deposit
Assets:
Available-for-sale debt investments:	663	439
Money market funds
Assets:
Cash equivalents:	5,398	3,334
Commercial paper
Assets:
Cash equivalents:	129	468
Corporate debt securities
Assets:
Cash equivalents:	4	25
Certificates of deposit
Assets:
Cash equivalents:	0	14
Level 1
Assets:
Marketable equity securities	339	481
Derivative assets	0	0
Total	6,675	5,128
Liabilities:
Derivative liabilities	0	0
Total	0	0
Level 1 \| Money market funds
Assets:
Other current assets:	750	750
Other assets:	188	563
Level 1 \| U.S. government securities
Assets:
Available-for-sale debt investments:	0	0
Level 1 \| U.S. government agency securities
Assets:
Available-for-sale debt investments:	0	0
Level 1 \| Non-U.S. government and agency securities
Assets:
Available-for-sale debt investments:	0	0
Level 1 \| Corporate debt securities
Assets:
Available-for-sale debt investments:	0	0
Level 1 \| U.S. agency mortgage-backed securities
Assets:
Available-for-sale debt investments:	0	0
Level 1 \| Commercial paper
Assets:
Available-for-sale debt investments:	0	0
Level 1 \| Certificates of deposit
Assets:
Available-for-sale debt investments:	0	0
Level 1 \| Money market funds
Assets:
Cash equivalents:	5,398	3,334
Level 1 \| Commercial paper
Assets:
Cash equivalents:	0	0
Level 1 \| Corporate debt securities
Assets:
Cash equivalents:	0	0
Level 1 \| Certificates of deposit
Assets:
Cash equivalents:	0	0
Level 2
Assets:
Marketable equity securities	0	0
Derivative assets	105	64
Total	8,196	10,436
Liabilities:
Derivative liabilities	70	74
Total	70	74
Level 2 \| Money market funds
Assets:
Other current assets:	0	0
Other assets:	0	0
Level 2 \| U.S. government securities
Assets:
Available-for-sale debt investments:	2,148	2,353
Level 2 \| U.S. government agency securities
Assets:
Available-for-sale debt investments:	111	221
Level 2 \| Non-U.S. government and agency securities
Assets:
Available-for-sale debt investments:	364	371
Level 2 \| Corporate debt securities
Assets:
Available-for-sale debt investments:	3,204	3,677
Level 2 \| U.S. agency mortgage-backed securities
Assets:
Available-for-sale debt investments:	736	1,781
Level 2 \| Commercial paper
Assets:
Available-for-sale debt investments:	732	1,023
Level 2 \| Certificates of deposit
Assets:
Available-for-sale debt investments:	663	439
Level 2 \| Money market funds
Assets:
Cash equivalents:	0	0
Level 2 \| Commercial paper
Assets:
Cash equivalents:	129	468
Level 2 \| Corporate debt securities
Assets:
Cash equivalents:	4	25
Level 2 \| Certificates of deposit
Assets:
Cash equivalents:	$ 0	$ 14

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