Financial Instruments - Activity Related to the Company's Investment Portfolio and Available-for-sale Debt Securities Contractual Maturities (Details) - USD ($) $ in Millions	3 Months Ended
Jul. 31, 2020	Jul. 26, 2019	Apr. 24, 2020
Activities Related to Debt Securities Portfolio
Proceeds from sales	$ 2,403	$ 1,567
Gross realized gains	5	4
Gross realized losses	(6)	$ (8)
AFS Debt Maturities
Due in one year or less	1,764
Due after one year through five years	3,049
Due after five years through ten years	1,677
Due after ten years	58
Fair Value	$ 6,548		$ 6,841

Fair value of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), with single maturity date and allocated without single maturity date, maturing in sixth through tenth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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