Fair Value - Assets and Liabilities Measured at Fair Value on Recurring Basis (Details) - USD ($) $ in Millions	Jan. 27, 2024	Jul. 29, 2023
Assets:
Available-for-sale debt investments:	$ 11,530	$ 15,592
Marketable equity securities	426	431
Derivative assets	50	32
Total	24,672	25,214
Liabilities:
Derivative liabilities	70	75
Total	70	75
Money market funds
Assets:
Other current assets:	563	188
Other assets:	938	1,313
U.S. government securities
Assets:
Available-for-sale debt investments:	2,397	3,526
U.S. government agency securities
Assets:
Available-for-sale debt investments:	352	423
Non-U.S. government and agency securities
Assets:
Available-for-sale debt investments:	364	363
Corporate debt securities
Assets:
Available-for-sale debt investments:	5,140	6,914
U.S. agency mortgage-backed securities
Assets:
Available-for-sale debt investments:	1,931	2,205
Commercial paper
Assets:
Available-for-sale debt investments:	828	1,484
Certificates of deposit
Assets:
Available-for-sale debt investments:	518	677
Money market funds
Assets:
Cash equivalents:	10,103	6,496
Commercial paper
Assets:
Cash equivalents:	1,023	1,090
Certificates of deposit
Assets:
Cash equivalents:	2	47
Corporate debt securities
Assets:
Cash equivalents:	30	25
Non-U.S. government and agency securities
Assets:
Cash equivalents:	7	0
Level 1
Assets:
Marketable equity securities	426	431
Derivative assets	0	0
Total	12,030	8,428
Liabilities:
Derivative liabilities	0	0
Total	0	0
Level 1 \| Money market funds
Assets:
Other current assets:	563	188
Other assets:	938	1,313
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:	10,103	6,496
Level 1 \| Commercial paper
Assets:
Cash equivalents:	0	0
Level 1 \| Certificates of deposit
Assets:
Cash equivalents:	0	0
Level 1 \| Corporate debt securities
Assets:
Cash equivalents:	0	0
Level 1 \| Non-U.S. government and agency securities
Assets:
Cash equivalents:	0	0
Level 2
Assets:
Marketable equity securities	0	0
Derivative assets	50	32
Total	12,642	16,786
Liabilities:
Derivative liabilities	70	75
Total	70	75
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:	2,397	3,526
Level 2 \| U.S. government agency securities
Assets:
Available-for-sale debt investments:	352	423
Level 2 \| Non-U.S. government and agency securities
Assets:
Available-for-sale debt investments:	364	363
Level 2 \| Corporate debt securities
Assets:
Available-for-sale debt investments:	5,140	6,914
Level 2 \| U.S. agency mortgage-backed securities
Assets:
Available-for-sale debt investments:	1,931	2,205
Level 2 \| Commercial paper
Assets:
Available-for-sale debt investments:	828	1,484
Level 2 \| Certificates of deposit
Assets:
Available-for-sale debt investments:	518	677
Level 2 \| Money market funds
Assets:
Cash equivalents:	0	0
Level 2 \| Commercial paper
Assets:
Cash equivalents:	1,023	1,090
Level 2 \| Certificates of deposit
Assets:
Cash equivalents:	2	47
Level 2 \| Corporate debt securities
Assets:
Cash equivalents:	30	25
Level 2 \| Non-U.S. government and agency securities
Assets:
Cash equivalents:	$ 7	$ 0

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