Financial Instruments - Activity Related to the Company's Debt Securities Portfolio and Available-for-sale Debt Securities Contractual Maturities (Details) - USD ($) $ in Millions	12 Months Ended
Apr. 24, 2020	Apr. 26, 2019	Apr. 27, 2018
AFS Gross Realized Gain (Loss)
Proceeds from sales	$ 9,559	$ 3,718	$ 3,309
Gross realized gains	25	18	27
Gross realized losses	(22)	(62)	$ (21)
AFS Debt Maturities
Due in one year or less	2,190
Due after one year through five years	2,854
Due after five years through ten years	1,733
Due after ten years	64
Total debt securities	$ 6,841	$ 5,499

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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