Income Taxes - Deferred Tax Assets and Liabilities (Details) - USD ($) $ in Thousands	Jan. 31, 2021	Jan. 31, 2020	Jan. 31, 2019
Deferred tax assets
Net operating loss carryforwards	$ 289,889	$ 166,083
Research and other credit carryforwards	22,778	15,355
Intangible assets	0	78
Stock-based compensation	20,154	8,716
Deferred revenue	21,595	21,012
Accrued expenses	7,791	2,555
Operating lease liabilities	10,718	0
Capitalized research and development	63,158	0
Other, net	0	950
Gross deferred assets	436,083	214,749
Less: Valuation allowance	(413,828)	(207,596)	$ (120,400)
Total deferred tax assets	22,255	7,153
Deferred tax liabilities
Property and equipment, net	(4,446)	(2,534)
Capitalized Commissions	(2,960)	(4,456)
Intangible assets	(3,697)	0
Operating right-of-use assets	(9,610)	0
Other, net	(302)	0
Total deferred tax liabilities	(21,015)	(6,990)
Net deferred tax assets (liabilities)	$ 1,240	$ 163

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from in-process research and development costs expensed in connection with a business combination.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible operating loss carryforwards.

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Amount, before allocation of valuation allowance, of deferred tax asset attributable to deductible temporary differences from provisions, reserves, allowances, and accruals, classified as other.

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Amount of deferred tax liability attributable to taxable temporary differences from property, plant, and equipment.

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