Revenue - Summary of Components of Deferred Revenue and Financed Unearned Services Revenue (Detail) - USD ($) $ in Millions	Apr. 26, 2019	Apr. 27, 2018	Apr. 28, 2017
Contract With Customer Liability [Line Items]
Deferred revenue and financed unearned services revenue	$ 3,668	$ 3,363	$ 3,213
Short-term	1,825	1,712
Long-term	1,843	1,651
Deferred product revenue
Contract With Customer Liability [Line Items]
Deferred revenue and financed unearned services revenue	84	107
Deferred services revenue
Contract With Customer Liability [Line Items]
Deferred revenue and financed unearned services revenue	3,502	3,134
Financed unearned services revenue
Contract With Customer Liability [Line Items]
Deferred revenue and financed unearned services revenue	$ 82	$ 122

Amount of obligation to transfer good or service to customer for which consideration has been received or is receivable, classified as noncurrent.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 8
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=109196051&loc=SL49130549-203045

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=82913815&loc=SL49130532-203044

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=82913815&loc=SL49130531-203044

Name:	us-gaap_ContractWithCustomerLiabilityNoncurrent
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant