Balance Sheet and Other Details (Details) - USD ($) $ in Millions	May 01, 2021	Jul. 25, 2020	Apr. 25, 2020	Jul. 27, 2019
Cash, cash equivalents, and restricted cash:
Cash and cash equivalents	$ 7,350	$ 11,809
Restricted cash included in other current assets	6	0
Restricted cash included in other assets	3	3
Total cash, cash equivalents, and restricted cash	7,359	11,812	$ 10,370	$ 11,772
Inventories:
Raw materials	723	456
Work in process	37	25
Finished goods:
Deferred cost of sales	73	59
Manufactured finished goods	546	542
Total finished goods	619	601
Service-related spares	188	184
Demonstration systems	12	16
Total	1,579	1,282
Property, Plant and Equipment [Line Items]
Total gross property and equipment	11,009	11,014
Less: accumulated depreciation and amortization	(8,642)	(8,561)
Net	2,367	2,453
Deferred revenue:
Deferred revenue:	20,889	20,446
Current	11,492	11,406
Noncurrent	9,397	9,040
Remaining Performance Obligations:
Remaining performance obligation	28,138	28,354
Product
Deferred revenue:
Deferred revenue:	8,698	7,895
Remaining Performance Obligations:
Remaining performance obligation	11,903	11,261
Service
Deferred revenue:
Deferred revenue:	12,191	12,551
Remaining Performance Obligations:
Remaining performance obligation	16,235	17,093
Land, buildings, and building and leasehold improvements
Property, Plant and Equipment [Line Items]
Total gross property and equipment	4,309	4,252
Computer equipment and related software
Property, Plant and Equipment [Line Items]
Total gross property and equipment	867	875
Production, engineering, and other equipment
Property, Plant and Equipment [Line Items]
Total gross property and equipment	5,146	5,163
Operating lease assets
Property, Plant and Equipment [Line Items]
Total gross property and equipment	311	337
Less: accumulated depreciation and amortization	(187)	(198)
Net	124	139
Furniture, fixtures and other
Property, Plant and Equipment [Line Items]
Total gross property and equipment	$ 376	$ 387