Net Loss Per Share - Summary of Calculation of Basic and Diluted Net Loss Per Share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Numerator:
Net loss	$ (43,148)	$ (9,333)	$ (97,760)	$ (19,065)
Denominator:
Weighted-average shares used in computing net loss per share, basic and diluted	122,614	114,572	121,397	112,734
Net loss per share, basic and diluted	$ (0.35)	$ (0.08)	$ (0.81)	$ (0.17)