Derivatives and Currency Exchange Risk Management - Gains Losses Recognized in AOCI, Net Investment Hedges (Details) - USD ($) $ in Millions	3 Months Ended
Jul. 26, 2019	Jul. 27, 2018
Derivative Instruments, Gain (Loss) [Line Items]
Recognized in AOCI, Net investment hedges	$ 99
Recognized in AOCI, Net investment hedges		$ 0
Currency exchange rate contracts \| Net investment hedges
Derivative Instruments, Gain (Loss) [Line Items]
Recognized in AOCI, Net investment hedges	$ 99
Recognized in AOCI, Net investment hedges		$ 0

Amount, after tax and adjustments, of gain (loss) from increase (decrease) in value of excluded component of derivative designated and qualifying as hedge. Adjustments include, but are not limited to, reclassifications for sale and settlement, and amounts recognized under systematic and rational method.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4C
-Subparagraph (bb)
-URI http://asc.fasb.org/extlink&oid=109980867&loc=SL5624171-113959

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 10A
-Subparagraph (dd)
-URI http://asc.fasb.org/extlink&oid=118930883&loc=SL7669646-108580

Name:	us-gaap_OtherComprehensiveIncomeLossDerivativeExcludedComponentIncreaseDecreaseAfterAdjustmentsAndTax
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration