CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS (Unaudited) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Income Statement [Abstract]
Revenue	$ 132,565	$ 119,605	$ 262,762	$ 227,496
Costs and expenses
Cost of revenue	45,049	40,063	94,616	73,582
Sales and marketing	59,983	38,622	118,115	75,575
General and administrative	30,246	16,105	59,981	30,591
Product development	55,752	37,526	111,824	70,981
Restructuring costs	10,861	493	10,838	3,225
Amortization of purchased intangibles	923	374	1,822	749
Total costs and expenses	202,814	133,183	397,196	254,703
Loss from operations	(70,249)	(13,578)	(134,434)	(27,207)
Other (expense) income, net:
Interest expense, net	(682)	(9,281)	(2,114)	(18,410)
Other (expense) income, net	(3,266)	2,338	(3,206)	3,050
Total other expense, net	(3,948)	(6,943)	(5,320)	(15,360)
Loss before provision for (benefit from) income taxes	(74,197)	(20,521)	(139,754)	(42,567)
Provision for (benefit from) income taxes	1,214	598	1,021	(253)
Net loss	$ (75,411)	$ (21,119)	$ (140,775)	$ (42,314)
Net loss per share of common stock:
Basic net loss per common share (in dollars per share)	$ (0.98)	$ (0.31)	$ (1.84)	$ (0.62)
Diluted net loss per common share (in dollars per share)	$ (0.98)	$ (0.31)	$ (1.84)	$ (0.62)
Weighted-average shares used to compute net loss per share:
Weighted average shares outstanding used in basic net loss per common share calculation (in shares)	77,290,465	69,057,129	76,555,518	68,482,653
Weighted average shares outstanding used in diluted net loss per common share calculation (in shares)	77,290,465	69,057,129	76,555,518	68,482,653