Goodwill and Other Intangible Assets - Changes in the Carrying Amount of Goodwill (Details) $ in Millions	6 Months Ended
Oct. 27, 2017 USD ($)
Goodwill [Roll Forward]
Beginning balance	$ 38,515
Goodwill as a result of acquisitions	15
Purchase accounting adjustments	54
Currency and other adjustments, net	493
Ending balance	39,077
Cardiac and Vascular Group
Goodwill [Roll Forward]
Beginning balance	6,651
Goodwill as a result of acquisitions	0
Purchase accounting adjustments	54
Currency and other adjustments, net	48
Ending balance	6,753
Minimally Invasive Therapies Group
Goodwill [Roll Forward]
Beginning balance	20,411
Goodwill as a result of acquisitions	0
Purchase accounting adjustments	0
Currency and other adjustments, net	405
Ending balance	20,816
Restorative Therapies Group
Goodwill [Roll Forward]
Beginning balance	9,600
Goodwill as a result of acquisitions	9
Purchase accounting adjustments	0
Currency and other adjustments, net	41
Ending balance	9,650
Diabetes Group
Goodwill [Roll Forward]
Beginning balance	1,853
Goodwill as a result of acquisitions	6
Purchase accounting adjustments	0
Currency and other adjustments, net	(1)
Ending balance	$ 1,858

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6388280&loc=d3e13770-109266

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=77989000&loc=SL49117168-202975

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Amount of increase in asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized resulting from a business combination.

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Amount of foreign currency translation gain (loss) which increases (decreases) an asset representing future economic benefits from other assets acquired in a business combination that are not individually identified and separately recognized.

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Amount of increase (decrease) from adjustments after acquisition date under purchase accounting of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 25
-Paragraph 16
-URI http://asc.fasb.org/extlink&oid=84229725&loc=d3e961-128460

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (g)
-URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267

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