Stock-Based Compensation (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Oct. 30, 2020	Oct. 25, 2019	Oct. 30, 2020	Oct. 25, 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation expense	$ 140	$ 108	$ 210	$ 169
Income tax benefits	(24)	(19)	(36)	(29)
Total stock-based compensation expense, net of tax	116	89	174	140
Cost of products sold
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation expense	14	10	21	16
Research and development expense
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation expense	15	13	23	20
Selling, general, and administrative expense
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation expense	111	85	166	133
Stock options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation expense	43	31	51	40
Restricted stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation expense	88	71	138	113
Employee stock purchase plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation expense	$ 9	$ 6	$ 21	$ 16

Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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