Goodwill and Other Intangible Assets - Changes in the Carrying Amount of Goodwill (Details) $ in Millions	3 Months Ended
Jul. 26, 2019 USD ($)
Goodwill [Roll Forward]
Beginning balance	$ 39,959
Goodwill as a result of acquisitions	65
Purchase accounting adjustments	5
Currency translation and other	53
Ending balance	40,082
Cardiac and Vascular Group
Goodwill [Roll Forward]
Beginning balance	6,854
Goodwill as a result of acquisitions	0
Purchase accounting adjustments	6
Currency translation and other	6
Ending balance	6,866
Minimally Invasive Therapies Group
Goodwill [Roll Forward]
Beginning balance	20,381
Goodwill as a result of acquisitions	0
Purchase accounting adjustments	1
Currency translation and other	56
Ending balance	20,438
Restorative Therapies Group
Goodwill [Roll Forward]
Beginning balance	10,821
Goodwill as a result of acquisitions	65
Purchase accounting adjustments	(2)
Currency translation and other	(9)
Ending balance	10,875
Diabetes Group
Goodwill [Roll Forward]
Beginning balance	1,903
Goodwill as a result of acquisitions	0
Purchase accounting adjustments	0
Currency translation and other	0
Ending balance	$ 1,903

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.

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-Name Accounting Standards Codification
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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.

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