Income Taxes - Schedule of Deferred Tax Assets and Liabilities (Details) - USD ($) $ in Thousands	Jan. 31, 2021	Jan. 31, 2020
Deferred tax assets:
Net operating losses carryforwards	$ 479,564	$ 157,995
Tax credit carryforwards	72,138	14,892
Stock-based compensation	49,548	4,437
Lease liabilities	50,834	50,624
Other	19,368	1,651
Total deferred tax assets	671,452	229,599
Less: valuation allowance	(599,603)	(165,067)
Net deferred tax assets	71,849	64,532
Deferred tax liabilities:
Capitalized commissions	(21,506)	(17,698)
Operating lease right-of-use assets	(50,343)	(46,834)
Total deferred tax liabilities	(71,849)	(64,532)
Net deferred tax assets (liabilities)	$ 0	$ 0