Description of Business - Additional Information (Detail) (USD $) In Thousands, except Share data, unless otherwise specified	0 Months Ended	12 Months Ended
	Jul. 03, 2012	Jan. 31, 2014	Jan. 31, 2013
Schedule Of Common Stock [Line Items]
Proceeds received from initial public offering	$ 34,576		$ 34,576
Underwriting discounts and commissions	2,917
Issuance expenses incurred in offering	4,174
Conversion ratio of preferred stock to common stock	Two thirteenths
Initial Public Offering [Member]
Schedule Of Common Stock [Line Items]
Issued common stock in public offering	4,166,667
Public offering price per share	$ 10.00
Underwriting discounts and commissions	$ 2,917