Property and Equipment, Net - Property and Equipment (Details) - USD ($) $ in Thousands	Jul. 31, 2020	Jan. 31, 2020
Property Plant And Equipment [Line Items]
Total property and equipment, gross	$ 51,144	$ 42,018
Less: accumulated depreciation and amortization	(27,546)	(23,216)
Property and equipment, net	23,598	18,802
Furniture and equipment
Property Plant And Equipment [Line Items]
Total property and equipment, gross	9,628	6,767
Software development costs
Property Plant And Equipment [Line Items]
Total property and equipment, gross	38,780	33,326
Leasehold improvements
Property Plant And Equipment [Line Items]
Total property and equipment, gross	1,994	1,880
Construction in progress
Property Plant And Equipment [Line Items]
Total property and equipment, gross	$ 742	$ 45