CONSOLIDATED STATEMENTS OF OPERATIONS - USD ($) shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Income Statement [Abstract]
Revenue	$ 218,309	$ 212,765	$ 192,197
Costs and expenses:
Cost of revenue	41,613	38,981	28,813
Research and development	149,998	127,073	97,096
Sales and marketing	122,925	123,182	106,430
General and administrative	76,057	67,733	54,664
Total costs and expenses	390,593	356,969	287,003
Loss from operations	(172,284)	(144,204)	(94,806)
Interest income	25,780	9,304	177
Other income (expense), net	(505)	(1,343)	(539)
Loss before income taxes	(147,009)	(136,243)	(95,168)
Provision for income taxes	756	1,673	157
Net loss	$ (147,765)	$ (137,916)	$ (95,325)
Net loss per share attributable to Class A and Class B common stockholders, basic (in USD per share)	$ (0.39)	$ (0.36)	$ (0.65)
Net loss per share attributable to Class A and Class B common stockholders, diluted (in USD per share)	$ (0.39)	$ (0.36)	$ (0.65)
Weighted average shares used in computing net loss per share attributable to Class A and Class B common stockholders, basic (in shares)	379,254	378,731	146,337
Weighted average shares used in computing net loss per share attributable to Class A and Class B common stockholders, diluted (in shares)	379,254	378,731	146,337