Summary of Stock Option Activity (Detail)	6 Months Ended
	Jul. 29, 2012
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Balance at January 29, 2012, shares	934,696
Granted, shares	0
Exercised, shares	(309,006)
Canceled, shares	(680)
Balance at July 29, 2012, shares	625,010