Stockholders' Equity - Reconciliation of Retained Earnings (Accumulated Deficit) (Detail) - USD ($) $ in Millions	3 Months Ended
Jul. 31, 2015	Jul. 25, 2014
Retained Earnings Adjustments [Line Items]
Beginning balance	$ 53
Net loss	(30)	$ 88
Repurchases of common stock	(430)
Ending balance	(31)
Retained Earnings
Retained Earnings Adjustments [Line Items]
Repurchases of common stock	$ (54)

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

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The cumulative amount of the reporting entity's undistributed earnings or deficit.

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Equity impact of the value of stock that has been repurchased and retired during the period. The excess of the purchase price over par value can be charged against retained earnings (once the excess is fully allocated to additional paid in capital).

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