Stockholders' Equity - Reconciliation of Retained Earnings (Detail) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Jan. 29, 2016	Jan. 23, 2015	Jan. 29, 2016	Jan. 23, 2015
Retained Earnings Adjustments [Line Items]
Beginning balance			$ 53
Net income	$ 153	$ 177	237	$ 425
Repurchases of common stock			(698)
Dividends paid			(159)	(157)
Ending balance	$ 51		51
Retained Earnings
Retained Earnings Adjustments [Line Items]
Repurchases of common stock			(164)
Dividends paid			$ (75)	$ (105)

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

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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