Net Loss Per Share - Schedule of Antidilutive Securities Excluded from the Computation of Diluted Net loss per share (Details) - shares	12 Months Ended
	Jan. 31, 2022	Jan. 31, 2021	Jan. 31, 2020
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per share (in shares)	12,527,352	10,309,699	12,278,679
Stock options to purchase common stock | Class A Common Stock
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per share (in shares)	778,172	1,340,476	2,145,462
Stock options to purchase common stock | Class B Common Stock
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per share (in shares)	2,391,439	3,759,063	5,076,831
Unvested restricted stock units
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per share (in shares)	3,680,895	3,864,504	2,914,575
Early exercised stock options
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per share (in shares)	102	5,032	29,532
Shares underlying the conversion option of the 2024 Notes (conversion spread only prior to the adoption of ASU 2020-06) | 2024 Notes
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per share (in shares)	231,637	889,755	2,112,279
Shares underlying the conversion option of the 2024 Notes (conversion spread only prior to the adoption of ASU 2020-06) | 2026 Notes
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per share (in shares)	5,445,107	450,869	0