Stock-Based Compensation (Details) - USD ($) $ in Millions	3 Months Ended
Jul. 26, 2019	Jul. 27, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation expense	$ 61	$ 64
Income tax benefits	(10)	(11)
Total stock-based compensation expense, net of tax	51	53
Cost of products sold
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation expense	6	6
Research and development expense
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation expense	7	8
Selling, general, and administrative expense
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation expense	48	50
Stock options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation expense	9	18
Restricted stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation expense	42	36
Employee stock purchase plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation expense	$ 10	$ 10

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

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