Incentive Stock Rights - Additional Information (Detail) (USD $)	3 Months Ended						12 Months Ended
	Jan. 31, 2014	Oct. 31, 2013	Jul. 31, 2013	Apr. 30, 2013	Jan. 31, 2012	Jul. 31, 2010	Jan. 31, 2014	Jun. 24, 2010
Class of Stock
Incentive stock purchase right adoption date						Jun. 24, 2010
Dividend distribution of rights declared for each outstanding share of common stock								1
Record date for distribution of rights	Dec. 10, 2013	Sep. 10, 2013	Jun. 10, 2013	Mar. 22, 2013		Jul. 06, 2010
Incentive stock purchase right amendment date			Jun. 28, 2013		Dec. 23, 2011
Right issuable with each new share of common stock	1						1
Number of shares called by rights								0.0001
Incentive stock purchase price	$ 90						$ 90
Percentage of common stock acquired to initiate exercise of incentive stock rights, minimum							15.00%
Percentage of common stock acquired to initiate exercise of incentive stock rights certain passive institutional investors							20.00%
Percent of incentive stock right exercise price for value of the entity's common stock received upon exercise of incentive stock right							200.00%
Date on which rights expire							Jun. 30, 2015
Rights redemption price							$ 0.001