Balance Sheet and Other Details - Remaining Performance Obligations (Details) - USD ($) $ in Millions	Apr. 30, 2022	Jul. 31, 2021
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Remaining performance obligation	$ 30,205	$ 30,893
Deferred revenue	22,293	22,164
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2021-08-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Remaining performance obligation		$ 16,289
Period for amount to be recognized as revenue		12 months
Amount to be recognized as revenue over next 12 months		53.00%
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2022-05-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Remaining performance obligation	$ 16,241
Period for amount to be recognized as revenue	12 months
Amount to be recognized as revenue over next 12 months	54.00%
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2022-07-31
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Remaining performance obligation		$ 14,604
Period for amount to be recognized as revenue
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2023-04-30
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Remaining performance obligation	$ 13,964
Period for amount to be recognized as revenue
Unbilled Contract Revenue
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Remaining performance obligation	$ 7,912	$ 8,729
Product
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Remaining performance obligation	13,416	13,270
Deferred revenue	9,835	9,416
Service
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Remaining performance obligation	16,789	17,623
Deferred revenue	$ 12,458	$ 12,748