Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands	Jan. 31, 2020	Jan. 31, 2019
Statement of Financial Position [Abstract]
Allowance for doubtful accounts	$ 810	$ 2,360
Redeemable convertible preferred stock, par value per share (in dollars per share)	$ 0.000005	$ 0.000005
Redeemable convertible preferred stock, shares authorized (in shares)	100,000,000	41,810,231
Redeemable convertible preferred stock, shares issued (in shares)	0	41,273,345
Redeemable convertible preferred stock, shares outstanding (in shares)	0	41,273,345
Redeemable convertible preferred stock, liquidation preference		$ 203,861
Common stock, par value per share (in dollars per share)	$ 0.000005	$ 0.000005
Common stock, shares authorized (in shares)	1,000,000,000	85,000,000
Common stock, shares issued (in shares)	77,793,540	23,189,921
Common stock, shares outstanding (in shares)	77,793,540	23,189,921

Amount of allowance for credit loss on accounts receivable, classified as current.

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