Description of Business and Significant Accounting Policies - Additional Information (Detail) - USD ($) $ in Millions	3 Months Ended			6 Months Ended
	Oct. 28, 2016	Jul. 29, 2016	Oct. 30, 2015	Oct. 28, 2016	Oct. 30, 2015
New Accounting Pronouncements Or Change In Accounting Principle [Line Items]
Provision for income taxes	$ 33		$ 30	$ 61	$ 38
Accounting Standards Update 2016-09
New Accounting Pronouncements Or Change In Accounting Principle [Line Items]
Provision for income taxes				$ 17
Accounting Standards Update 2016-09 | Account for Forfeitures As Occur
New Accounting Pronouncements Or Change In Accounting Principle [Line Items]
Cumulative-effect impact to retained earnings		$ 7
Accounting Standards Update 2016-09 | Forfeiture Rate Policy Change On Outstanding Stock Based Awards
New Accounting Pronouncements Or Change In Accounting Principle [Line Items]
Cumulative-effect adjustment to retained earnings		(3)
Accounting Standards Update 2016-09 | Previously Unrecognized Tax Benefits
New Accounting Pronouncements Or Change In Accounting Principle [Line Items]
Cumulative-effect adjustment to retained earnings		$ 17