Financial Instruments - Activity Related to the Company's Investment Portfolio, Equity and Other Investments (Details) - USD ($) $ in Millions	12 Months Ended
Apr. 24, 2020	Apr. 26, 2019	Apr. 27, 2018
Marketable Securities [Line Items]
Proceeds from sales	$ 9,574	$ 4,683	$ 4,227
Recognized impairment losses	0	0	(227)
Equity Investments
Marketable Securities [Line Items]
Proceeds from sales	15	964	918
Gross gains	17	134	18
Gross losses	(30)	(30)	(4)
Recognized impairment losses	$ (4)	$ (45)	$ (231)

Gain on Investments

No definition available.

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- Definition

Loss on Investments

+ References

No definition available.

+ Details

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- Definition

The amount by which the fair value of an investment is less than the amortized cost basis or carrying amount of that investment at the balance sheet date and the decline in fair value is deemed to be other than temporary, before considering whether or not such amount is recognized in earnings or other comprehensive income.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 45
-Paragraph 8A
-URI http://asc.fasb.org/extlink&oid=121553693&loc=SL6284422-111562

+ Details

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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- Definition

The cash inflow associated with the sale, maturity and collection of all investments such as debt, security and so forth during the period.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 12
-URI http://asc.fasb.org/extlink&oid=121586364&loc=d3e3179-108585

+ Details

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- Details

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