Segment and Geographic Information (Details) - USD ($) $ in Millions	3 Months Ended
Jul. 31, 2020	Jul. 26, 2019
Segment Operating Profit
Segment operating profit	$ 673	$ 1,485
Interest expense	(171)	(609)
Amortization of intangible assets	(440)	(440)
Restructuring and associated costs	(53)	(47)
Certain litigation charges, net	88	(47)
Income before income taxes	584	977
Geographic Information
Net sales	6,507	7,493
Ireland
Geographic Information
Net sales	24	20
United States
Geographic Information
Net sales	3,351	3,918
Rest of world
Geographic Information
Net sales	3,132	3,555
Total other countries, excluding Ireland
Geographic Information
Net sales	6,483	7,473
Operating Segments
Segment Operating Profit
Segment operating profit	1,840	2,768
Segment Reconciling Items
Segment Operating Profit
Interest expense	(171)	(609)
Other non-operating income, net	82	101
Amortization of intangible assets	(440)	(440)
Corporate	(365)	(307)
Centralized distribution costs	(399)	(345)
Restructuring and associated costs	(128)	(124)
Acquisition-related items	105	(19)
Certain litigation charges, net	88	(47)
IPR&D charges	(10)	0
Debt tender premium and other charges	0	7
Medical device regulations	(18)	(8)
Cardiac & Vascular Group
Geographic Information
Net sales	2,433	2,790
Cardiac & Vascular Group \| United States
Geographic Information
Net sales	1,206	1,361
Cardiac & Vascular Group \| Operating Segments
Segment Operating Profit
Segment operating profit	759	1,055
Minimally Invasive Therapies Group
Geographic Information
Net sales	1,801	2,100
Minimally Invasive Therapies Group \| United States
Geographic Information
Net sales	722	913
Minimally Invasive Therapies Group \| Operating Segments
Segment Operating Profit
Segment operating profit	455	771
Restorative Therapies Group
Geographic Information
Net sales	1,712	2,012
Restorative Therapies Group \| United States
Geographic Information
Net sales	1,136	1,338
Restorative Therapies Group \| Operating Segments
Segment Operating Profit
Segment operating profit	523	793
Diabetes Group
Geographic Information
Net sales	562	592
Diabetes Group \| United States
Geographic Information
Net sales	287	306
Diabetes Group \| Operating Segments
Segment Operating Profit
Segment operating profit	$ 103	$ 149

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