Computation of Net Income (Loss) Per Share - Calculation of Basic and Diluted Net Income (Loss) Per Share (Detail) (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended		9 Months Ended
	Oct. 31, 2013	Oct. 31, 2012	Oct. 31, 2013	Oct. 31, 2012
Numerator:
Net income (loss)	$ 516	$ 159	$ (823)	$ 1,103
Denominator:
Weighted average common shares, basic	13,341,235	13,264,018	13,318,839	6,133,987
Dilutive effect of:
Options to purchase common and preferred stock	1,351,169	1,365,658		1,357,992
Warrants to purchase common stock	12,118	9,588		51,443
Convertible preferred stock				4,760,301
Weighted average common shares, diluted	14,704,522	14,639,264	13,318,839	12,303,723
Basic net income (loss) per share	$ 0.04	$ 0.01	$ (0.06)	$ 0.18
Diluted net income (loss) per share	$ 0.04	$ 0.01	$ (0.06)	$ 0.09