Net Income Per Share - Narrative (Detail)	3 Months Ended		6 Months Ended
	Oct. 27, 2013	Oct. 28, 2012	Oct. 27, 2013	Oct. 28, 2012
Earnings Per Share Disclosure [Line Items]
Number of shares of common stock excluded from the computation of basic net income	61,667	123,335	61,667	123,335
Stock Options [Member]
Earnings Per Share Disclosure [Line Items]
Number of common stock options excluded from the computation of diluted net income per share		2,000		2,000