Stock-Based Compensation (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Jan. 24, 2020	Jan. 25, 2019	Jan. 24, 2020	Jan. 25, 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation expense	$ 66	$ 60	$ 235	$ 228
Income tax benefits	(11)	(8)	(40)	(40)
Total stock-based compensation expense, net of tax	55	52	195	188
Cost of products sold
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation expense	6	5	22	23
Research and development expense
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation expense	9	8	29	29
Selling, general, and administrative expense
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation expense	51	47	184	176
Stock options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation expense	12	11	52	62
Restricted stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation expense	46	43	159	144
Employee stock purchase plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation expense	$ 8	$ 6	$ 24	$ 22

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

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