Revenue - Disaggregation of Net Sales by Segment and Division (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Jan. 24, 2020	Jan. 25, 2019	Jan. 24, 2020	Jan. 25, 2019
Disaggregation of Revenue [Line Items]
Net sales	$ 7,717	$ 7,546	$ 22,916	$ 22,411
Cardiac and Vascular Group
Disaggregation of Revenue [Line Items]
Net sales	2,819	2,786	8,464	8,455
Cardiac and Vascular Group | Cardiac Rhythm & Heart Failure
Disaggregation of Revenue [Line Items]
Net sales	1,393	1,397	4,201	4,295
Cardiac and Vascular Group | Coronary & Structural Heart
Disaggregation of Revenue [Line Items]
Net sales	948	913	2,844	2,736
Cardiac and Vascular Group | Aortic, Peripheral, & Venous
Disaggregation of Revenue [Line Items]
Net sales	478	476	1,420	1,424
Minimally Invasive Therapies Group
Disaggregation of Revenue [Line Items]
Net sales	2,176	2,124	6,418	6,223
Minimally Invasive Therapies Group | Surgical Innovations
Disaggregation of Revenue [Line Items]
Net sales	1,474	1,434	4,345	4,224
Minimally Invasive Therapies Group | Respiratory, Gastrointestinal, & Renal
Disaggregation of Revenue [Line Items]
Net sales	702	690	2,073	1,999
Restorative Therapies Group
Disaggregation of Revenue [Line Items]
Net sales	2,111	2,026	6,235	5,968
Restorative Therapies Group | Brain Therapies
Disaggregation of Revenue [Line Items]
Net sales	795	732	2,307	2,107
Restorative Therapies Group | Spine
Disaggregation of Revenue [Line Items]
Net sales	674	655	2,023	1,963
Restorative Therapies Group | Specialty Therapies
Disaggregation of Revenue [Line Items]
Net sales	340	325	996	956
Restorative Therapies Group | Pain Therapies
Disaggregation of Revenue [Line Items]
Net sales	303	314	910	942
Diabetes Group
Disaggregation of Revenue [Line Items]
Net sales	$ 610	$ 610	$ 1,798	$ 1,765