The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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Stockholders' Equity - Reconciliation of Retained Earnings (Accumulated Deficit) (Detail) - USD ($) $ in Millions	3 Months Ended		9 Months Ended		188 Months Ended
	Jan. 25, 2019	Jan. 26, 2018	Jan. 25, 2019	Jan. 26, 2018	Jan. 25, 2019
Retained Earnings Adjustments [Line Items]
Beginning balance			$ (9)
Net income	$ 249	$ (479)	773	$ (174)
Repurchases of common stock			(1,611)		$ (11,200)
Ending balance	0		0		0
Retained Earnings (Accumulated Deficit)
Retained Earnings Adjustments [Line Items]
Cumulative-effect of new accounting principle	$ (51)		(51)		$ (51)
Net income			773
Repurchases of common stock			$ (713)