Stockholders' Equity - Number and Value of Shares Netted for Employee Taxes (Detail) - Restricted Stock Units - USD ($) shares in Millions, $ in Millions	9 Months Ended
Jan. 29, 2016	Jan. 23, 2015
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares withheld for taxes	2	1
Fair value of shares withheld	$ 47	$ 51

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

No definition available.

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