Stockholders' Equity - Activity Related to Stock Options (Detail) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	12 Months Ended
	Apr. 29, 2016	Apr. 24, 2015	Apr. 25, 2014
Number of Shares
Beginning balance, Number of Shares	12	15	19
Options granted, Number of Shares		2	3
Options assumed in acquisition, Number of Shares	2
Options exercised, Number of Shares	(2)	(5)	(6)
Options forfeited and expired, Number of Shares	(3)		(1)
Ending balance, Number of Shares	9	12	15
Options vested and expected to vest, Number of Shares	9
Options Exercisable, Number of Shares	6
Weighted-Average Exercise Price
Beginning balance, Weighted-Average Exercise Price	$ 37.74	$ 34.10	$ 31.27
Options granted, Weighted-Average Exercise Price		36.64	38.26
Options assumed in acquisition, Weighted-Average Exercise Price	5.20
Options exercised, Weighted-Average Exercise Price	19.64	25.25	25.83
Options forfeited and expired, Weighted-Average Exercise Price	38.27	42.42	42.47
Ending balance, Weighted-Average Exercise Price	34.01	$ 37.74	$ 34.10
Options vested and expected to vest, Weighted-Average Exercise Price	34.52
Options Exercisable, Weighted-Average Exercise Price	$ 39.98
Weighted-Average Remaining Contractual Term and Aggregate Intrinsic Value
Outstanding, Weighted-Average Remaining Contractual Term	3 years 6 months 7 days
Options vested and expected to vest, Weighted-Average Remaining Contractual Term	3 years 4 months 24 days
Exercisable, Weighted-Average Remaining Contractual Term	2 years 2 months 19 days
Outstanding, Aggregate Intrinsic Value	$ 29
Options vested and expected to vest, Aggregate Intrinsic Value	26
Exercisable, Aggregate Intrinsic Value	$ 3