Stock-Based Compensation (Details) - USD ($) $ in Millions	3 Months Ended
Jul. 31, 2020	Jul. 26, 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation expense	$ 70	$ 61
Income tax benefits	(11)	(10)
Total stock-based compensation expense, net of tax	59	51
Cost of products sold
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation expense	7	6
Research and development expense
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation expense	8	7
Selling, general, and administrative expense
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation expense	55	48
Stock options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation expense	8	9
Restricted stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation expense	50	42
Employee stock purchase plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation expense	$ 12	$ 10

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

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