Net loss per share - Schedule of Computation (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended				9 Months Ended
	Sep. 30, 2021		Sep. 30, 2020	[1]	Sep. 30, 2021		Sep. 30, 2020
Numerator:
Net loss	$ (30,383)	[1]	$ (5,388)		$ (51,439)	[1]	$ (15,718)	[2]
Denominator:
Weighted-average shares used to compute net loss per share, basic (in shares)	118,640,565		113,203,074		117,983,463		106,333,836	[1]
Weighted-average shares used to compute net loss per share, diluted (in shares)	118,640,565		113,203,074		117,983,463		106,333,836	[1]
Basic net loss per share (in dollars per share)	$ (0.26)		$ (0.05)		$ (0.44)		$ (0.15)	[1]
Diluted net loss per share (in dollars per share)	$ (0.26)		$ (0.05)		$ (0.44)		$ (0.15)	[1]

[1] Certain prior period amounts have been revised to correct immaterial errors. See Note 1 for more information.

[2] Certain prior period amounts have been revised to correct immaterial errors. See Note 1 for more information.