Financial Instruments - Activity Related to the Company's Investment Portfolio and Debt Securities Contractual Maturities (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Jan. 28, 2022	Jan. 29, 2021	Jan. 28, 2022	Jan. 29, 2021	Apr. 30, 2021
Activities Related to Debt Securities Portfolio
Proceeds from sales	$ 2,481	$ 2,406	$ 7,052	$ 6,740
Gross realized gains	3	4	15	12
Gross realized losses	(6)	$ (4)	(10)	$ (11)
Debt Securities, Available-for-sale, Fair Value, Fiscal Year Maturity [Abstract]
Due in one year or less	2,208		2,208
Due after one year through five years	3,337		3,337
Due after five years through ten years	1,540		1,540
Due after ten years	691		691
Total	$ 7,776		$ 7,776		$ 7,257

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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