Net Loss Per Share Attributable to Common Stockholders - Antidilutive Securities (Details) - shares shares in Thousands	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Total	25,931	18,312
Options to purchase common stock
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Total	17,832	14,953
RSU
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Total	7,958	3,309
Employee stock purchase plan
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Total	91	0
Restricted stock
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Total	50	50