Special Charges - Additional Information (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Apr. 30, 2013		Jan. 31, 2013
Disclosure Special Charges Additional Information [Abstract]
Percentage of termination benefit paid during the period	26.00%
Accrued special charges ending balance	$ 5,125	[1]	$ 4,917
Long-term portion of accrued lease termination fees and other facility costs, net of sublease income	2,110
Short-term portion of accrued special charges	$ 3,015

[1] Of the $5,125 total accrued special charges as of April 30, 2013, $2,110 represents the long-term portion, which primarily includes accrued lease termination fees and other facility costs, net of sublease income and other long-term costs. The remaining balance of $3,015 represents the short-term portion of accrued special charges.