Net Loss Per Share - Computation of Basic and Diluted Loss Per Share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended						9 Months Ended
	Sep. 30, 2023	Jun. 30, 2023	Mar. 31, 2023	Sep. 30, 2022	Jun. 30, 2022	Mar. 31, 2022	Sep. 30, 2023	Sep. 30, 2022
Numerator:
Net loss	$ (13,932)			$ (26,993)			$ (78,029)	$ (95,140)
Net income attributable to the redeemable noncontrolling interest	0	$ 0	$ 0	0	$ 0	$ 164	0	164
Net (loss) income attributable to noncontrolling interests	(210)			(137)			(470)	211
Net loss attributable to holders of Class A, Class B, and Class C common stock	$ (13,722)			$ (26,856)			$ (77,559)	$ (95,515)
Denominator:
Weighted average common shares outstanding, basic (in shares)	145,053			138,939			142,585	137,591
Weighted average common shares outstanding, diluted (in shares)	145,053			138,939			142,585	137,591
Net loss per common share, basic (in dollars per share)	$ (0.09)			$ (0.19)			$ (0.54)	$ (0.69)
Net loss per common share, diluted (in dollars per share)	$ (0.09)			$ (0.19)			$ (0.54)	$ (0.69)