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Supplemental Financial Information - Additional Information (Detail) - USD ($) $ in Millions		6 Months Ended
	Aug. 29, 2019	Oct. 25, 2019	Oct. 26, 2018	Apr. 26, 2019
Property Plant And Equipment [Line Items]
Net book value		$ 746		$ 759
Cash proceeds from properties sold		$ 96	$ 0
Lenovo NetApp Technology Limited (“LNTL”)
Property Plant And Equipment [Line Items]
Non-controlling equity interest, ownership percentage		49.00%
Other non current assets		$ 77		$ 78
Properties Sold
Property Plant And Equipment [Line Items]
Cash proceeds from properties sold	$ 96
Gain on sale of properties, net of direct selling costs	38
Other Current Assets
Property Plant And Equipment [Line Items]
Net book value	$ 53