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Supplemental Financial Information - Additional Information (Detail) - USD ($) $ in Millions		3 Months Ended	12 Months Ended
	Aug. 26, 2019	Apr. 24, 2020	Apr. 30, 2021	Apr. 24, 2020	Apr. 26, 2019
Property Plant And Equipment [Line Items]
Net book value		$ 727	$ 525	$ 727
Cash proceeds from properties sold			371	96	$ 0
Lenovo NetApp Technology Limited (“LNTL”)
Property Plant And Equipment [Line Items]
Non-controlling equity interest, ownership percentage					49.00%
Aggregate net book value of contributed assets			7
Fair value of equity interest			80
Gain on derecognition of assets			73
Book value of investments		67	71	$ 67
Investments, other-than-temporary impairment charge		$ 10
Properties Sold
Property Plant And Equipment [Line Items]
Net book value			210
Cash proceeds from properties sold			365
Below market leases			7
Gain on sale of properties, net of direct selling costs			$ 156
Land
Property Plant And Equipment [Line Items]
Net book value	$ 53
Cash proceeds from properties sold	96
Gain on sale of properties, net of direct selling costs	$ 38