Fair Value - Assets and Liabilities Measured at Fair Value on Recurring Basis (Details) - USD ($) $ in Millions	Jan. 29, 2022	Jul. 31, 2021
Assets:
Available-for-sale debt investments:	$ 14,161	$ 15,206
U.S. government securities
Assets:
Available-for-sale debt investments:	1,687	1,794
U.S. government agency securities
Assets:
Available-for-sale debt investments:	140	152
Corporate debt securities
Assets:
Available-for-sale debt investments:	8,988	8,910
Non-U.S. government and agency securities
Assets:
Available-for-sale debt investments:		3
Commercial paper
Assets:
Available-for-sale debt investments:	614	1,190
Certificates of deposit
Assets:
Available-for-sale debt investments:	209	295
Fair value, measurements, recurring
Assets:
Marketable equity securities	221	137
Derivative assets	77	126
Total	18,621	22,327
Liabilities:
Derivative liabilities	38	20
Total	38	20
Fair value, measurements, recurring \| Money market funds
Assets:
Other assets:	750	750
Fair value, measurements, recurring \| U.S. government securities
Assets:
Available-for-sale debt investments:	1,687	1,794
Fair value, measurements, recurring \| U.S. government agency securities
Assets:
Available-for-sale debt investments:	140	152
Fair value, measurements, recurring \| Corporate debt securities
Assets:
Available-for-sale debt investments:	8,988	8,910
Fair value, measurements, recurring \| U.S. agency mortgage-backed securities
Assets:
Available-for-sale debt investments:	2,523	2,862
Fair value, measurements, recurring \| Non-U.S. government and agency securities
Assets:
Available-for-sale debt investments:	0	3
Fair value, measurements, recurring \| Commercial paper
Assets:
Available-for-sale debt investments:	614	1,190
Fair value, measurements, recurring \| Certificates of deposit
Assets:
Available-for-sale debt investments:	209	295
Fair value, measurements, recurring \| Money market funds
Assets:
Cash equivalents:	3,402	5,694
Fair value, measurements, recurring \| Commercial paper
Assets:
Cash equivalents:	10	114
Fair value, measurements, recurring \| U.S. government securities
Assets:
Cash equivalents:	0	300
Fair value, measurements, recurring \| Level 1
Assets:
Marketable equity securities	221	137
Derivative assets	0	0
Total	4,373	6,581
Liabilities:
Derivative liabilities	0	0
Total	0	0
Fair value, measurements, recurring \| Level 1 \| Money market funds
Assets:
Other assets:	750	750
Fair value, measurements, recurring \| Level 1 \| U.S. government securities
Assets:
Available-for-sale debt investments:	0	0
Fair value, measurements, recurring \| Level 1 \| U.S. government agency securities
Assets:
Available-for-sale debt investments:	0	0
Fair value, measurements, recurring \| Level 1 \| Corporate debt securities
Assets:
Available-for-sale debt investments:	0	0
Fair value, measurements, recurring \| Level 1 \| U.S. agency mortgage-backed securities
Assets:
Available-for-sale debt investments:	0	0
Fair value, measurements, recurring \| Level 1 \| Non-U.S. government and agency securities
Assets:
Available-for-sale debt investments:	0	0
Fair value, measurements, recurring \| Level 1 \| Commercial paper
Assets:
Available-for-sale debt investments:	0	0
Fair value, measurements, recurring \| Level 1 \| Certificates of deposit
Assets:
Available-for-sale debt investments:	0	0
Fair value, measurements, recurring \| Level 1 \| Money market funds
Assets:
Cash equivalents:	3,402	5,694
Fair value, measurements, recurring \| Level 1 \| Commercial paper
Assets:
Cash equivalents:	0	0
Fair value, measurements, recurring \| Level 1 \| U.S. government securities
Assets:
Cash equivalents:	0	0
Fair value, measurements, recurring \| Level 2
Assets:
Marketable equity securities	0	0
Derivative assets	77	126
Total	14,248	15,746
Liabilities:
Derivative liabilities	38	20
Total	38	20
Fair value, measurements, recurring \| Level 2 \| Money market funds
Assets:
Other assets:	0	0
Fair value, measurements, recurring \| Level 2 \| U.S. government securities
Assets:
Available-for-sale debt investments:	1,687	1,794
Fair value, measurements, recurring \| Level 2 \| U.S. government agency securities
Assets:
Available-for-sale debt investments:	140	152
Fair value, measurements, recurring \| Level 2 \| Corporate debt securities
Assets:
Available-for-sale debt investments:	8,988	8,910
Fair value, measurements, recurring \| Level 2 \| U.S. agency mortgage-backed securities
Assets:
Available-for-sale debt investments:	2,523	2,862
Fair value, measurements, recurring \| Level 2 \| Non-U.S. government and agency securities
Assets:
Available-for-sale debt investments:	0	3
Fair value, measurements, recurring \| Level 2 \| Commercial paper
Assets:
Available-for-sale debt investments:	614	1,190
Fair value, measurements, recurring \| Level 2 \| Certificates of deposit
Assets:
Available-for-sale debt investments:	209	295
Fair value, measurements, recurring \| Level 2 \| Money market funds
Assets:
Cash equivalents:	0	0
Fair value, measurements, recurring \| Level 2 \| Commercial paper
Assets:
Cash equivalents:	10	114
Fair value, measurements, recurring \| Level 2 \| U.S. government securities
Assets:
Cash equivalents:	$ 0	$ 300

Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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Amount excluding accrued interest, of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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