Property and Equipment, Net - Schedule of Property and Equipment (Detail) - USD ($) $ in Thousands	Jan. 31, 2021	Jan. 31, 2020
Property Plant And Equipment [Line Items]
Property and equipment, gross	$ 22,008	$ 19,987
Less: accumulated depreciation and amortization	(16,478)	(14,373)
Total property and equipment, net	5,530	5,614
Computer equipment and software [Member]
Property Plant And Equipment [Line Items]
Property and equipment, gross	11,525	10,282
Machinery and equipment [Member]
Property Plant And Equipment [Line Items]
Property and equipment, gross	6,946	6,317
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	2,237	2,356
Construction in progress [Member]
Property Plant And Equipment [Line Items]
Property and equipment, gross	$ 331	$ 63

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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