Stock Option Activity under Two Thousand Six Plan (Detail) (Employee Stock Plan, 2006 Plan, USD $)	12 Months Ended
	Feb. 01, 2014
Employee Stock Plan, 2006 Plan
Number of Shares
Outstanding at beginning of year	376,374
Options granted	2,781,938
Options canceled	(426,743)
Options exercised	(10,000)
Outstanding at end of year	2,721,569
Vested and expected to vest at end of year	1,439,330
Options exercisable at end of year	317,588
Weighted-average Exercise price per Option
Outstanding at beginning of year	$ 4.31
Options granted	$ 5.05
Options canceled	$ 5.05
Options exercised	$ 3.98
Outstanding at end of year	$ 4.95
Vested and expected to vest at end of year	$ 4.89
Options exercisable at end of year	$ 4.57
Weighted-average Remaining Contractual Term
Outstanding options at end of year	8 years 10 months 24 days
Vested and expected to vest at end of year	8 years 6 months
Options exercisable at end of year	5 years 6 months
Aggregate Intrinsic Value
Outstanding options at end of year	$ 1,264,148
Vested and expected to vest at end of year	814,934
Options exercisable at end of year	$ 348,606