Income Taxes - Statutory Federal Income Tax Rate (Detail) - USD ($) $ in Millions	12 Months Ended
Apr. 26, 2019	Apr. 27, 2018	Apr. 28, 2017
Effective Income Tax Rate Reconciliation, Amount [Abstract]
Tax computed at federal statutory rate	$ 266	$ 366	$ 218
State income taxes, net of federal benefit	16	18	8
Foreign earnings in lower tax jurisdictions	(84)	(108)	(100)
Stock-based compensation	(19)	(23)	16
Research and development credits	(17)	(10)	(8)
Resolution of income tax examinations	(48)	0	0
Domestic production activities deduction	(13)	(7)	(4)
Global minimum tax on intangible income	22	0	0
Tax rate changes	0	108	5
Non-taxable gain on joint venture formation	(14)	0	0
Transition tax	(5)	732	0
Other	(5)	7	5
Provision for income taxes	$ 99	$ 1,083	$ 140

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Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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