Available-for-Sale Debt and Equity Investments - Summary of Available-for-Sale Investments (Details) - USD ($) $ in Millions	Jul. 30, 2022	Jul. 31, 2021
Schedule of Investments [Line Items]
Amortized Cost	$ 12,467	$ 14,978
Gross Unrealized Gains	2	268
Gross Unrealized and Credit Losses	(522)	(40)
Fair Value	11,947	15,206
U.S. government securities
Schedule of Investments [Line Items]
Amortized Cost	1,287	1,773
Gross Unrealized Gains	0	21
Gross Unrealized and Credit Losses	(49)	0
Fair Value	1,238	1,794
U.S. government agency securities
Schedule of Investments [Line Items]
Amortized Cost	142	152
Gross Unrealized Gains	0	0
Gross Unrealized and Credit Losses	(4)	0
Fair Value	138	152
Non-U.S. government and agency securities
Schedule of Investments [Line Items]
Amortized Cost	272	3
Gross Unrealized Gains	0	0
Gross Unrealized and Credit Losses	0	0
Fair Value	272	3
Corporate debt securities
Schedule of Investments [Line Items]
Amortized Cost	8,127	8,727
Gross Unrealized Gains	2	213
Gross Unrealized and Credit Losses	(311)	(30)
Fair Value	7,818	8,910
U.S. agency mortgage-backed securities
Schedule of Investments [Line Items]
Amortized Cost	2,134	2,838
Gross Unrealized Gains	0	34
Gross Unrealized and Credit Losses	(158)	(10)
Fair Value	1,976	2,862
Commercial paper
Schedule of Investments [Line Items]
Amortized Cost	255	1,190
Gross Unrealized Gains	0	0
Gross Unrealized and Credit Losses	0	0
Fair Value	255	1,190
Certificates of deposit
Schedule of Investments [Line Items]
Amortized Cost	250	295
Gross Unrealized Gains	0	0
Gross Unrealized and Credit Losses	0	0
Fair Value	$ 250	$ 295

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

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-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
-Section 50
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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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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

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