Acquisitions and Acquisition-Related Items - Reconciliation of Beginning and Ending Balances of Contingent Consideration (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Oct. 27, 2017	Oct. 28, 2016	Oct. 27, 2017	Oct. 28, 2016
Reconciliation of Beginning and Ending Balances of Contingent Milestone Payments Associated with Acquisitions [Roll Forward]
Beginning Balance	$ 242	$ 379	$ 246	$ 377
Purchase price contingent consideration	15	11	15	32
Payments	(43)	(25)	(46)	(39)
Change in fair value	(24)	(80)	(25)	(85)
Ending Balance	$ 190	$ 285	$ 190	$ 285