Financial Instruments - Narrative (Details) - USD ($)	3 Months Ended	6 Months Ended
Oct. 30, 2020	Oct. 25, 2019	Oct. 30, 2020	Oct. 25, 2019	Apr. 24, 2020
Investments [Abstract]
Debt securities in credit loss position	$ 0		$ 0		$ 0
Reductions for available-for-sale or held-to-maturity securities sold	0	$ 0	0	$ 0
Gain (Loss) on Securities [Line Items]
Impairment charges incurred	0
Equity Securities and Other Investments
Gain (Loss) on Securities [Line Items]
Net gains (losses) recognized	0	14,000,000	12,000,000	14,000,000
Net unrealized gains (losses) on equity and other investments still held		14,000,000	12,000,000	14,000,000
Impairment charges incurred	$ 0	$ 2,000,000	$ 2,000,000	$ 3,000,000

Amount of realized and unrealized gain (loss) on investment.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
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-Publisher FASB
-Name Accounting Standards Codification
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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

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
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The cumulative amount of credit losses recognized in earnings related to debt securities held for which a portion of an other than temporary impairment (OTTI) was recognized in other comprehensive income (a component of shareholders' equity).

+ References

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This item represents reductions in the cumulative amount of credit losses recognized in earnings for an other than temporary impairment (OTTI) of a debt security because of the sale of impaired securities during the period.

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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.

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Amount of unrealized gain (loss) on investment.

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