Segment and Geographic Information (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Oct. 26, 2018	Oct. 27, 2017	Oct. 26, 2018	Oct. 27, 2017
Segment Reporting Information [Line Items]
Net sales	$ 7,481	$ 7,050	$ 14,865	$ 14,440
Income before Income Taxes by Reportable Segment
Interest expense	(241)	(273)	(483)	(559)
Amortization of intangible assets	(445)	(460)	(891)	(914)
Restructuring and associated costs	(24)	(8)	(86)	(16)
Certain litigation charges	0	0	(103)	0
Gain on sale of businesses	0	697	0	697
Income before income taxes	1,355	1,728	2,535	2,923
Ireland
Segment Reporting Information [Line Items]
Net sales	22	22	44	42
United States
Segment Reporting Information [Line Items]
Net sales	4,045	3,734	7,909	7,776
Rest of world
Segment Reporting Information [Line Items]
Net sales	3,414	3,294	6,912	6,622
Total other countries, excluding Ireland
Segment Reporting Information [Line Items]
Net sales	7,459	7,028	14,821	14,398
Operating Segments
Income before Income Taxes by Reportable Segment
Segment EBITA	2,913	2,706	5,680	5,383
Segment Reconciling Items
Income before Income Taxes by Reportable Segment
Interest expense	(241)	(273)	(483)	(559)
Interest income	66	100	147	192
Amortization of intangible assets	(445)	(460)	(891)	(914)
Corporate	(335)	(339)	(646)	(616)
Centralized distribution costs	(482)	(486)	(929)	(928)
Restructuring and associated costs	(77)	(18)	(190)	(32)
Acquisition-related items	(4)	(18)	(40)	(71)
Gain/(loss) on minority investments	(25)	0	85	0
IPR&D charges	(15)	0	(15)	0
Certain litigation charges	0	0	(103)	0
Exit of business	0	0	(80)	0
Divestiture-related items	0	(67)	0	(115)
Gain on sale of businesses	0	697	0	697
Contribution to Medtronic Foundation	0	(80)	0	(80)
Hurricane Maria	0	(34)	0	(34)
Cardiac and Vascular Group
Segment Reporting Information [Line Items]
Net sales	2,858	2,773	5,669	5,419
Cardiac and Vascular Group \| United States
Segment Reporting Information [Line Items]
Net sales	1,482	1,423	2,871	2,756
Cardiac and Vascular Group \| Operating Segments
Income before Income Taxes by Reportable Segment
Segment EBITA	1,140	1,104	2,191	2,115
Minimally Invasive Therapies Group
Segment Reporting Information [Line Items]
Net sales	2,047	1,952	4,099	4,438
Minimally Invasive Therapies Group \| United States
Segment Reporting Information [Line Items]
Net sales	872	795	1,729	2,040
Minimally Invasive Therapies Group \| Operating Segments
Income before Income Taxes by Reportable Segment
Segment EBITA	792	761	1,569	1,636
Restorative Therapies Group
Segment Reporting Information [Line Items]
Net sales	1,993	1,863	3,942	3,672
Restorative Therapies Group \| United States
Segment Reporting Information [Line Items]
Net sales	1,357	1,258	2,651	2,479
Restorative Therapies Group \| Operating Segments
Income before Income Taxes by Reportable Segment
Segment EBITA	805	750	1,571	1,430
Diabetes Group
Segment Reporting Information [Line Items]
Net sales	583	462	1,155	911
Diabetes Group \| United States
Segment Reporting Information [Line Items]
Net sales	334	258	658	501
Diabetes Group \| Operating Segments
Income before Income Taxes by Reportable Segment
Segment EBITA	$ 176	$ 91	$ 349	$ 202

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