Goodwill and Other Intangible Assets - Changes in the Carrying Amount of Goodwill (Details) $ in Millions	3 Months Ended
Jul. 31, 2020 USD ($)
Goodwill [Roll Forward]
Beginning balance	$ 39,841
Purchase accounting adjustments	3
Currency translation and other	870
Ending balance	40,714
Cardiac & Vascular Group
Goodwill [Roll Forward]
Beginning balance	6,831
Purchase accounting adjustments	0
Currency translation and other	83
Ending balance	6,914
Minimally Invasive Therapies Group
Goodwill [Roll Forward]
Beginning balance	20,176
Purchase accounting adjustments	0
Currency translation and other	693
Ending balance	20,869
Restorative Therapies Group
Goodwill [Roll Forward]
Beginning balance	10,920
Purchase accounting adjustments	3
Currency translation and other	93
Ending balance	11,016
Diabetes Group
Goodwill [Roll Forward]
Beginning balance	1,914
Purchase accounting adjustments	0
Currency translation and other	1
Ending balance	$ 1,915

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/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(10)(1))
-URI http://asc.fasb.org/extlink&oid=120398452&loc=d3e534808-122878

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=120320667&loc=SL49117168-202975

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=99380562&loc=d3e13770-109266

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- Definition

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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 50
-Paragraph 1
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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://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 25
-Paragraph 16
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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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