Stock-Based Compensation (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Oct. 30, 2015	Oct. 24, 2014	Oct. 30, 2015	Oct. 24, 2014
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation expense	$ 113	$ 48	$ 209	$ 82
Income tax benefits	(34)	(14)	(63)	(23)
Total stock-based compensation expense, net of tax	79	34	146	59
Cost of products sold [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation expense	14	4	26	8
Research and development expense [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation expense	12	9	20	15
Selling, general and administrative expense [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation expense	65	35	114	59
Restructuring charges, net [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation expense	6	0	14	0
Acquisition-related items [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation expense	16	0	35	0
Stock options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation expense	62	14	119	20
Restricted stock awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation expense	46	31	80	54
Employee stock purchase plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation expense	$ 5	$ 3	$ 10	$ 8

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
-Subparagraph (SAB TOPIC 14.F)
-URI http://asc.fasb.org/extlink&oid=27013229&loc=d3e301413-122809

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5047-113901

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (h)(1)(i)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Staff Accounting Bulletin (SAB)
-Number Topic 14
-Section F

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
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-SubTopic 10
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