Basic and Diluted Net Loss Per Share (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended				6 Months Ended
	Jun. 30, 2021	Mar. 31, 2021	Jun. 30, 2020	Mar. 31, 2020	Jun. 30, 2021	Jun. 30, 2020
Numerator:
Net loss	$ (16,296)	$ (65,101)	$ (6,258)	$ (18,367)	$ (81,398)	$ (24,625)
Denominator:
Shares used in computing net loss attributable per share to common stockholders, basic	95,221,928		35,478,347		91,483,053	35,117,130
Shares used in computing net loss attributable per share to common stockholders, diluted	95,221,928		35,478,347		91,483,053	35,117,130
Net loss attributable per share to common stockholders:
Basic	$ (0.17)		$ (0.18)		$ (0.89)	$ (0.70)
Diluted	$ (0.17)		$ (0.18)		$ (0.89)	$ (0.70)