Summary of Stock-Based Compensation Expense Related to Common Stock and Common Stock Option Awards (Detail) (USD $)	3 Months Ended		9 Months Ended
	Oct. 31, 2013	Oct. 31, 2012	Oct. 31, 2013	Oct. 31, 2012
Summary Of Stock Based Compensation Expense Related To Common Stock and Common Stock Option Awards [Line Items]
Stock-based compensation expense	$ 357,969	$ 1,547,237	$ 2,026,682	$ 1,732,301
Cost of services
Summary Of Stock Based Compensation Expense Related To Common Stock and Common Stock Option Awards [Line Items]
Stock-based compensation expense	73,767	440,075	550,925	452,584
General and administrative
Summary Of Stock Based Compensation Expense Related To Common Stock and Common Stock Option Awards [Line Items]
Stock-based compensation expense	$ 284,203	$ 1,107,162	$ 1,475,757	$ 1,279,717