Available-for-Sale Debt and Equity Investments - Summary of Available-for-Sale Debt Investments (Details) - USD ($) $ in Millions	Apr. 30, 2022	Jul. 31, 2021
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	$ 13,431	$ 14,978
Gross Unrealized Gains	5	268
Gross Unrealized and Credit Losses	(522)	(40)
Fair Value	12,914	15,206
U.S. government securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	1,346	1,773
Gross Unrealized Gains	0	21
Gross Unrealized and Credit Losses	(46)	0
Fair Value	1,300	1,794
U.S. government agency securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	150	152
Gross Unrealized Gains	0	0
Gross Unrealized and Credit Losses	(4)	0
Fair Value	146	152
Non-U.S. government and agency securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	171	3
Gross Unrealized Gains	0	0
Gross Unrealized and Credit Losses	0	0
Fair Value	171	3
Corporate debt securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	8,770	8,727
Gross Unrealized Gains	5	213
Gross Unrealized and Credit Losses	(296)	(30)
Fair Value	8,479	8,910
U.S. agency mortgage-backed securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	2,234	2,838
Gross Unrealized Gains	0	34
Gross Unrealized and Credit Losses	(176)	(10)
Fair Value	2,058	2,862
Commercial paper
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	548	1,190
Gross Unrealized Gains	0	0
Gross Unrealized and Credit Losses	0	0
Fair Value	548	1,190
Certificates of deposit
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	212	295
Gross Unrealized Gains	0	0
Gross Unrealized and Credit Losses	0	0
Fair Value	$ 212	$ 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

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 http://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
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- Definition

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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