Summary of Stock Option Activity (Detail)	9 Months Ended
	Nov. 01, 2015 shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Balance at February 1, 2015, shares	107,000
Granted, shares	0
Exercised, shares	(68,500)
Cancelled, shares	0
Balance at November 1, 2015 shares	38,500