Employee Benefit Plans - Components of the Change in Pension Benefit Obligation (Detail) - USD ($)	12 Months Ended
	Jan. 31, 2018	Jan. 31, 2017	Jan. 31, 2016
Defined Benefit Pension Plans And Defined Benefit Postretirement Plans Disclosure [Abstract]
Projected benefit obligation, beginning of fiscal year	$ 530,000	$ 1,063,000
Service cost		238,000	$ 288,000
Interest cost		54,000	51,000
Actuarial gain		(801,000)	(435,000)
Foreign currency exchange rate changes		(24,000)
Termination of the Plan	(530,000)
Projected benefit obligation, end of fiscal year	$ 0	530,000	$ 1,063,000
Funded status at end of fiscal year		$ 530,000