Accrued Expenses and Other Current Liabilities (Details) - USD ($) $ in Thousands	Jan. 31, 2021	Jan. 31, 2020
Payables and Accruals [Abstract]
Accrued compensation	$ 62,451	$ 40,961
ESPP employee contributions	22,068	0
Accrued purchases of property and equipment	6,718	430
Accrued third-party cloud infrastructure expenses	6,648	8,360
Accrued professional services	6,628	5,200
Accrued taxes	4,498	2,352
Other	16,304	5,514
Total accrued expenses and other current liabilities	$ 125,315	$ 62,817