Property and Equipment, Net - Schedule of Property and Equipment (Detail) - USD ($) $ in Thousands	Apr. 30, 2017	Jan. 31, 2017
Property, Plant and Equipment [Line Items]
Total property and equipment	$ 27,373	$ 26,594
Less accumulated depreciation	(13,719)	(12,566)
Property and equipment, net	13,654	14,028
Computer Software and Equipment [Member]
Property, Plant and Equipment [Line Items]
Total property and equipment	23,467	23,321
Office Equipment and Furniture [Member]
Property, Plant and Equipment [Line Items]
Total property and equipment	1,551	1,549
Leasehold Improvements [Member]
Property, Plant and Equipment [Line Items]
Total property and equipment	1,634	1,629
Construction in Process [Member]
Property, Plant and Equipment [Line Items]
Total property and equipment	$ 721	$ 95