Severance and Other Restructuring Costs - Activity in Accrued Restructuring Liability (Detail) $ in Thousands	6 Months Ended
	Jul. 31, 2018 USD ($)
Restructuring Cost and Reserve [Line Items]
Accrual balance at the beginning of the period	$ 225
Restructuring charges incurred	(14)
Cash payments	(211)
Employee-Related Benefits [Member]
Restructuring Cost and Reserve [Line Items]
Accrual balance at the beginning of the period	61
Restructuring charges incurred	22
Cash payments	(83)
Closure of Leased Facilities [Member]
Restructuring Cost and Reserve [Line Items]
Accrual balance at the beginning of the period	135
Restructuring charges incurred	(7)
Cash payments	(128)
Other Restructuring [Member]
Restructuring Cost and Reserve [Line Items]
Accrual balance at the beginning of the period	29
Restructuring charges incurred	$ (29)