Stock Purchase and Award Plans , Stock-based Compensation Expense (Details) - USD ($) $ in Millions	12 Months Ended
Apr. 24, 2015	Apr. 25, 2014	Apr. 26, 2013
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense	$ 439	$ 145	$ 152
Income tax benefits	(138)	(40)	(43)
Stock-based compensation expense, net of tax	301	105	109
Cost of products sold
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense	23	14	12
Research and development expense
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense	29	27	31
Selling, general, and administrative expense
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense	128	104	109
Restructuring charges
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense	70	0	0
Acquisition-related items
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense	189	0	0
Stock options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense	140	34	44
Restricted stock awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense	284	98	96
Employees stock purchase plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense	$ 15	$ 13	$ 12

Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section S99

-Paragraph 1

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-Publisher SEC

-Name Staff Accounting Bulletin (SAB)

-Number Topic 14

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The amount of expense, net of income tax, recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

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The total recognized tax benefit related to compensation cost for equity-based payment arrangements recognized in income during the period.

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