Balance Sheet Components - Schedule of Accrued Expenses and Other Current Liabilities (Details) - USD ($) $ in Thousands	Jan. 31, 2020	Jan. 31, 2019
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Liabilities to employees and tax authorities from international employee stock sales	$ 49,287	$ 0
Accrued compensation and benefits	36,732	12,004
Accrued expenses	17,475	13,596
Operating lease liabilities, current	7,675	0
Other	11,523	6,656
Accrued expenses and other current liabilities	$ 122,692	$ 32,256