Available-for-Sale Debt and Equity Investments - Summary of Available-for-Sale Debt Investments (Details) - USD ($) $ in Millions	Jan. 28, 2023	Jul. 30, 2022
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	$ 13,356	$ 12,467
Gross Unrealized Gains	9	2
Gross Unrealized and Credit Losses	(593)	(522)
Fair Value	12,772	11,947
U.S. government securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	2,050	1,287
Gross Unrealized Gains	2	0
Gross Unrealized and Credit Losses	(54)	(49)
Fair Value	1,998	1,238
U.S. government agency securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	169	142
Gross Unrealized Gains	0	0
Gross Unrealized and Credit Losses	(5)	(4)
Fair Value	164	138
Non-U.S. government and agency securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	354	272
Gross Unrealized Gains	0	0
Gross Unrealized and Credit Losses	(1)	0
Fair Value	353	272
Corporate debt securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	7,480	8,127
Gross Unrealized Gains	5	2
Gross Unrealized and Credit Losses	(345)	(311)
Fair Value	7,140	7,818
U.S. agency mortgage-backed securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	2,013	2,134
Gross Unrealized Gains	2	0
Gross Unrealized and Credit Losses	(188)	(158)
Fair Value	1,827	1,976
Commercial paper
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	1,029	255
Gross Unrealized Gains	0	0
Gross Unrealized and Credit Losses	0	0
Fair Value	1,029	255
Certificates of deposit
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	261	250
Gross Unrealized Gains	0	0
Gross Unrealized and Credit Losses	0	0
Fair Value	$ 261	$ 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)
-URI https://asc.fasb.org/extlink&oid=126970911&loc=d3e27161-111563

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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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+ References

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