Summary of Significant Accounting Policies- Summary of Basic and Diluted Net Loss per Share Attributable to Common Stockholders (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2021	Sep. 30, 2021	Jun. 30, 2021	Mar. 31, 2021	Dec. 31, 2020	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Numerator:
Net loss	$ (10,363)	$ (12,692)	$ (13,972)	$ (11,636)	$ (10,258)	$ (8,026)	$ (6,976)	$ (7,585)	$ (48,663)	$ (32,845)	$ (47,339)
Net loss attributable to common stockholders									$ (48,663)	$ (32,845)	$ (47,339)
Denominator:
Weighted-average common shares – basic and diluted									67,956,739	32,506,679	22,180,868
Net loss per share attributable to common stockholders — basic and diluted	$ (0.13)	$ (0.17)	$ (0.24)	$ (0.21)	$ (0.24)	$ (0.22)	$ (0.26)	$ (0.31)	$ (0.72)	$ (1.01)	$ (2.13)