Severance and Other Restructuring Costs - Change in Severance Liability (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended	9 Months Ended
	Oct. 31, 2014	Oct. 31, 2014
Restructuring and Related Activities [Abstract]
Accrual balance at the beginning of the period	$ 213	$ 229
Severance charges accrued	1,186	1,878
Severance costs paid	(185)	(893)
Accrual balance as of October 31, 2014	$ 1,214	$ 1,214