Segment and Geographic Information (Details) - USD ($) $ in Millions	3 Months Ended
Jul. 26, 2019	Jul. 27, 2018
Segment Reporting Information [Line Items]
Net sales	$ 7,493	$ 7,384
Income before Income Taxes by Reportable Segment
Segment operating profit	1,485	1,236
Interest expense	(609)	(242)
Amortization of intangible assets	(440)	(446)
Restructuring and associated costs	(47)	(62)
Certain litigation charges	(47)	(103)
Income (loss) before income taxes	977	1,180
Ireland
Segment Reporting Information [Line Items]
Net sales	20	22
United States
Segment Reporting Information [Line Items]
Net sales	3,918	3,864
Rest of world
Segment Reporting Information [Line Items]
Net sales	3,555	3,498
Total other countries, excluding Ireland
Segment Reporting Information [Line Items]
Net sales	7,473	7,362
Operating Segments
Income before Income Taxes by Reportable Segment
Segment operating profit	2,768	2,763
Segment Reconciling Items
Income before Income Taxes by Reportable Segment
Interest expense	(609)	(242)
Other non-operating income, net	101	186
Amortization of intangible assets	(440)	(446)
Corporate	(307)	(303)
Centralized distribution costs	(345)	(446)
Restructuring and associated costs	(124)	(113)
Acquisition-related items	(19)	(36)
Certain litigation charges	(47)	(103)
Exit of businesses	0	(80)
Debt tender premium and other charges	7	0
Medical device regulations	(8)	0
Cardiac and Vascular Group
Segment Reporting Information [Line Items]
Net sales	2,790	2,811
Cardiac and Vascular Group \| United States
Segment Reporting Information [Line Items]
Net sales	1,361	1,389
Cardiac and Vascular Group \| Operating Segments
Income before Income Taxes by Reportable Segment
Segment operating profit	1,055	1,049
Minimally Invasive Therapies Group
Segment Reporting Information [Line Items]
Net sales	2,100	2,052
Minimally Invasive Therapies Group \| United States
Segment Reporting Information [Line Items]
Net sales	913	857
Minimally Invasive Therapies Group \| Operating Segments
Income before Income Taxes by Reportable Segment
Segment operating profit	771	776
Restorative Therapies Group
Segment Reporting Information [Line Items]
Net sales	2,012	1,949
Restorative Therapies Group \| United States
Segment Reporting Information [Line Items]
Net sales	1,338	1,294
Restorative Therapies Group \| Operating Segments
Income before Income Taxes by Reportable Segment
Segment operating profit	793	766
Diabetes Group
Segment Reporting Information [Line Items]
Net sales	592	572
Diabetes Group \| United States
Segment Reporting Information [Line Items]
Net sales	306	324
Diabetes Group \| Operating Segments
Income before Income Taxes by Reportable Segment
Segment operating profit	$ 149	$ 172

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