Stock-Based Compensation (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Jul. 27, 2012	Jul. 29, 2011
Stock-based Compensation Expense by Component and Classification
Stock-based compensation expense	$ 36	$ 41
Income tax benefits	(10)	(11)
Total stock-based compensation expense, net of tax	26	30
Cost of Products Sold
Stock-based Compensation Expense by Component and Classification
Stock-based compensation expense	3	3
Research and Development Expense
Stock-based Compensation Expense by Component and Classification
Stock-based compensation expense	7	7
Selling, General and Administrative Expense
Stock-based Compensation Expense by Component and Classification
Stock-based compensation expense	26	31
Stock Options
Stock-based Compensation Expense by Component and Classification
Stock-based compensation expense	11	15
Restricted Stock Awards
Stock-based Compensation Expense by Component and Classification
Stock-based compensation expense	21	22
Employee Stock Purchase Plan
Stock-based Compensation Expense by Component and Classification
Stock-based compensation expense	$ 4	$ 4