Restructuring - Termination Liability and Restructuring Reserve (Details) - USD ($) $ in Millions	3 Months Ended
Jul. 31, 2020	Jul. 26, 2019
Enterprise Excellence
Restructuring Reserve [Roll Forward]
Beginning balance	$ 112
Charges	79	$ 136
Cash payments	(100)
Accrual adjustments	(2)	$ (12)
Ending balance	89
Enterprise Excellence \| Employee Termination Benefits
Restructuring Reserve [Roll Forward]
Beginning balance	89
Charges	6
Cash payments	(26)
Accrual adjustments	0
Ending balance	69
Enterprise Excellence \| Associated Costs
Restructuring Reserve [Roll Forward]
Beginning balance	19
Charges	73
Cash payments	(72)
Accrual adjustments	0
Ending balance	20
Enterprise Excellence \| Other Costs
Restructuring Reserve [Roll Forward]
Beginning balance	4
Charges	0
Cash payments	(2)
Accrual adjustments	(2)
Ending balance	0
Simplification
Restructuring Reserve [Roll Forward]
Beginning balance	0
Charges	51
Cash payments	(1)
Ending balance	50
Simplification \| Employee Termination Benefits
Restructuring Reserve [Roll Forward]
Beginning balance	0
Charges	50
Cash payments	0
Ending balance	50
Simplification \| Associated Costs
Restructuring Reserve [Roll Forward]
Beginning balance	0
Charges	1
Cash payments	(1)
Ending balance	$ 0

Amount of cash payments made as the result of exit or disposal activities. Excludes payments associated with a discontinued operation or an asset retirement obligation.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 420
-SubTopic 10
-Section 50
-Paragraph 1
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-URI http://asc.fasb.org/extlink&oid=6394359&loc=d3e17939-110869

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
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-Section 45
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- Definition

Amount of expenses associated with exit or disposal activities pursuant to an authorized plan. Excludes expenses related to a discontinued operation or an asset retirement obligation.

+ References

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-Publisher FASB
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- Definition

Carrying amount (including both current and noncurrent portions of the accrual) as of the balance sheet date pertaining to a specified type of cost associated with exit from or disposal of business activities or restructuring pursuant to a duly authorized plan.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 420
-SubTopic 10
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- Definition

Amount of expense (reversal of expense) which increases (decreases) the restructuring reserve from an adjustment to a previously accrued restructuring liability.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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-SubTopic 10
-Section 50
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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

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