Goodwill and Other Intangible Assets - Carrying Amount and Accumulated Amortization of Intangible Assets (Details) - USD ($) $ in Millions	Oct. 26, 2018	Apr. 27, 2018
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount, Definite-lived	$ 29,380	$ 29,434
Accumulated Amortization	(9,032)	(8,201)
IPR&D
Indefinite-lived Intangible Assets [Line Items]
Gross Carrying Amount, Indefinite-lived	471	490
Customer-related
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount, Definite-lived	16,917	16,949
Accumulated Amortization	(3,611)	(3,139)
Purchased technology and patents
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount, Definite-lived	11,553	11,569
Accumulated Amortization	(4,784)	(4,441)
Trademarks and tradenames
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount, Definite-lived	821	822
Accumulated Amortization	(582)	(569)
Other
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount, Definite-lived	89	94
Accumulated Amortization	$ (55)	$ (52)