Net Loss Per Share Attributable to Common Stockholders - Schedule of Anti-dilutive Securities Outstanding in Common Stock Equivalent Excluded from Computation of Diluted Weighted Average Shares Outstanding (Details) - shares	9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020
Redeemable Convertible Preferred Stock Warrants
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per share, amount	77,842	77,842
Unvested Early Exercised Common Stock Options
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per share, amount	410,788
Options to Purchase Common Stock
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per share, amount	2,170,894	2,573,122
Redeemable Convertible Preferred Stock
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per share, amount	12,397,838	12,397,838