Stockholders' Equity - Amounts Reclassified Out of Accumulated Other Comprehensive Income (Loss) (Detail) - USD ($) $ in Millions	3 Months Ended
	Jul. 31, 2015	Jul. 25, 2014
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Operating expenses	$ 842	$ 778
Net revenues	1,335	1,489
Net income (loss)	(30)	88
Reclassification out of Accumulated Other Comprehensive Income
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Net income (loss)	2	2
Reclassification out of Accumulated Other Comprehensive Income | Recognized Losses on Defined Benefit Obligations
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Operating expenses	1	0
Reclassification out of Accumulated Other Comprehensive Income | Realized Losses on Cash Flow Hedges
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Net revenues	$ 1	$ 2