Net Income (Loss) Per Share - Summary of Antidilutive Potential Common Shares (Details) - shares	9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive potential common shares (in shares)	4,591,873	139,321,438
Convertible preferred stock
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive potential common shares (in shares)	0	109,090,908
Stock options exercised for promissory notes
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive potential common shares (in shares)	2,884,999	7,862,499
Shares issuable upon conversion of Athena convertible security
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive potential common shares (in shares)	334,946	0
Early exercised stock options
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive potential common shares (in shares)	879,600	19,800
Unvested RSAs
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive potential common shares (in shares)	242,316	1,908,687
Stock options
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive potential common shares (in shares)	23,736	20,439,544
Unvested RSUs
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive potential common shares (in shares)	2,828	0
ESPP
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive potential common shares (in shares)	223,448	0