Stock Based Compensation - Additional Information (Detail) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended	9 Months Ended
	Oct. 31, 2013	Oct. 31, 2013
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Weighted average grant date per share for stock options	$ 7.16	$ 6.78
Total unrecognized compensation cost	$ 2,711	$ 2,711
Weighted-average period		2 years 10 months 13 days