Available-for-Sale Debt and Equity Investments - Summary of Available-for-Sale Debt Investments (Details) - USD ($) $ in Millions	Apr. 29, 2023	Jul. 30, 2022
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	$ 15,438	$ 12,467
Gross Unrealized Gains	19	2
Gross Unrealized and Credit Losses	(559)	(522)
Fair Value	14,898	11,947
U.S. government securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	2,833	1,287
Gross Unrealized Gains	9	0
Gross Unrealized and Credit Losses	(42)	(49)
Fair Value	2,800	1,238
U.S. government agency securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	365	142
Gross Unrealized Gains	1	0
Gross Unrealized and Credit Losses	(4)	(4)
Fair Value	362	138
Non-U.S. government and agency securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	352	272
Gross Unrealized Gains	0	0
Gross Unrealized and Credit Losses	0	0
Fair Value	352	272
Corporate debt securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	7,587	8,127
Gross Unrealized Gains	8	2
Gross Unrealized and Credit Losses	(305)	(311)
Fair Value	7,290	7,818
U.S. agency mortgage-backed securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	2,221	2,134
Gross Unrealized Gains	1	0
Gross Unrealized and Credit Losses	(208)	(158)
Fair Value	2,014	1,976
Commercial paper
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	1,595	255
Gross Unrealized Gains	0	0
Gross Unrealized and Credit Losses	0	0
Fair Value	1,595	255
Certificates of deposit
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	485	250
Gross Unrealized Gains	0	0
Gross Unrealized and Credit Losses	0	0
Fair Value	$ 485	$ 250

Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax And Allowance For Credit Loss

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- Definition

Amount, before tax, of unrealized gain in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (b)
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- Definition

Amortized cost excluding accrued interest, before allowance for credit loss, of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 30
-Section 45
-Paragraph 1
-URI https://asc.fasb.org/extlink&oid=124258926&loc=SL82898722-210454

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- Definition

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).

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 30
-Section 45
-Paragraph 1
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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

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