Property and Equipment, Net - Schedule of Property and Equipment (Detail) - USD ($) $ in Thousands	Jul. 31, 2019	Jan. 31, 2019
Property Plant And Equipment [Line Items]
Property and equipment, gross	$ 19,101	$ 18,387
Less: accumulated depreciation and amortization	(12,996)	(11,659)
Total property and equipment, net	6,105	6,728
Computer equipment and software [Member]
Property Plant And Equipment [Line Items]
Property and equipment, gross	9,641	9,098
Machinery and equipment [Member]
Property Plant And Equipment [Line Items]
Property and equipment, gross	6,098	5,659
Furniture and fixtures [Member]
Property Plant And Equipment [Line Items]
Property and equipment, gross	969	969
Leasehold improvements [Member]
Property Plant And Equipment [Line Items]
Property and equipment, gross	2,343	2,331
Construction in progress [Member]
Property Plant And Equipment [Line Items]
Property and equipment, gross	$ 50	$ 330

Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

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Amount before accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

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