Revenue - Disaggregation of Net Sales by Market Geography for Each Segment (Details) - USD ($) $ in Millions	3 Months Ended
	Jul. 26, 2019	Jul. 27, 2018
Disaggregation of Revenue [Line Items]
Net sales	$ 7,493	$ 7,384
U.S.
Disaggregation of Revenue [Line Items]
Net sales	3,918	3,864
Non-U.S. Developed Markets
Disaggregation of Revenue [Line Items]
Net sales	2,377	2,406
Emerging Markets
Disaggregation of Revenue [Line Items]
Net sales	1,198	1,114
Cardiac and Vascular Group
Disaggregation of Revenue [Line Items]
Net sales	2,790	2,811
Cardiac and Vascular Group | U.S.
Disaggregation of Revenue [Line Items]
Net sales	1,361	1,389
Cardiac and Vascular Group | Non-U.S. Developed Markets
Disaggregation of Revenue [Line Items]
Net sales	930	947
Cardiac and Vascular Group | Emerging Markets
Disaggregation of Revenue [Line Items]
Net sales	499	475
Minimally Invasive Therapies Group
Disaggregation of Revenue [Line Items]
Net sales	2,100	2,052
Minimally Invasive Therapies Group | U.S.
Disaggregation of Revenue [Line Items]
Net sales	913	857
Minimally Invasive Therapies Group | Non-U.S. Developed Markets
Disaggregation of Revenue [Line Items]
Net sales	791	828
Minimally Invasive Therapies Group | Emerging Markets
Disaggregation of Revenue [Line Items]
Net sales	396	367
Restorative Therapies Group
Disaggregation of Revenue [Line Items]
Net sales	2,012	1,949
Restorative Therapies Group | U.S.
Disaggregation of Revenue [Line Items]
Net sales	1,338	1,294
Restorative Therapies Group | Non-U.S. Developed Markets
Disaggregation of Revenue [Line Items]
Net sales	426	428
Restorative Therapies Group | Emerging Markets
Disaggregation of Revenue [Line Items]
Net sales	248	227
Diabetes Group
Disaggregation of Revenue [Line Items]
Net sales	592	572
Diabetes Group | U.S.
Disaggregation of Revenue [Line Items]
Net sales	306	324
Diabetes Group | Non-U.S. Developed Markets
Disaggregation of Revenue [Line Items]
Net sales	231	203
Diabetes Group | Emerging Markets
Disaggregation of Revenue [Line Items]
Net sales	$ 55	$ 45