v3.21.1

Income taxes - Additional Information (Detail) - USD ($)	12 Months Ended
	Jan. 31, 2021	Jan. 31, 2020	Jan. 31, 2019
Operating Loss Carryforwards [Line Items]
(Provision for) benefit from income taxes	$ (49,000)	$ 1,780,000	$ 0
Effective tax rate	0.00%	8.00%	0.00%
Valuation allowance	$ (54,563,000)	$ (35,369,000)
Tax examination, penalties and interest accrued	0
Domestic Tax Authority
Operating Loss Carryforwards [Line Items]
Accumulated federal net operating loss carryforward	199,079,000	$ 124,512,000	$ 100,000,000
Foreign Tax Authority
Operating Loss Carryforwards [Line Items]
Accumulated federal net operating loss carryforward	$ 2,485,000

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- Definition

Amount of deferred tax assets for which it is more likely than not that a tax benefit will not be realized.

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The amount of estimated penalties and interest accrued as of the balance sheet date arising from income tax examinations.

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