Consolidated Statements of Operations - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Income Statement [Abstract]
Revenue	$ 514,800	$ 469,624	$ 366,620
Costs and expenses:
Cost of revenue	184,699	156,880	106,268
Sales and marketing	214,027	165,421	149,773
General and administrative	120,625	76,757	60,557
Product development	193,688	158,390	108,414
Restructuring costs	19,967	3,397	29,420
Amortization of purchased intangible assets	3,678	2,045	1,639
Total costs and expenses	736,684	562,890	456,071
Loss from operations	(221,884)	(93,266)	(89,451)
Other expense, net:
Interest expense, net	(352)	(37,406)	(14,334)
Other (expense) income, net	(1,784)	3,294	(1,343)
Total other expense, net	(2,136)	(34,112)	(15,677)
Loss before provision for (benefit from) income taxes	(224,020)	(127,378)	(105,128)
Provision for (benefit from) income taxes	1,727	(2,404)	2,466
Net loss	$ (225,747)	$ (124,974)	$ (107,594)
Net loss per share of common stock:
Basic	$ (3.03)	$ (1.80)	$ (1.63)
Diluted	$ (3.03)	$ (1.80)	$ (1.63)
Weighted-average shares used to compute net loss per share:
Basic	74,509,404	69,606,105	65,888,450
Diluted	74,509,404	69,606,105	65,888,450