Net Loss per Share Attributable to Common Stockholders - Schedule of Basic and Diluted Net Loss per Share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Numerator:
Net loss available to Class A and Class B common stockholders	$ (24,889)	$ (75,949)
Denominator:
Weighted average shares used to compute net loss per share available to Class A and Class B common stockholders, basic and diluted (in shares)	170,745	123,763
Net loss per share attributable to Class A and Class B common stockholders, basic and diluted (in dollars per share)	$ (0.15)	$ (0.61)