Condensed Consolidated Statements of Operations and Comprehensive Loss - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Income Statement [Abstract]
Net revenue	$ 108,891	$ 191,621	$ 557,349	$ 544,401
Costs of revenue	36,383	111,519	311,068	311,524
Gross profit	72,508	80,102	246,281	232,877
Operating expenses:
Compensation and benefits	115,846	105,887	390,393	304,103
Technology	13,930	13,422	41,674	37,960
Professional services	4,197	6,620	14,507	17,184
Occupancy	1,074	1,125	3,285	3,388
Depreciation and amortization	3,108	934	7,582	2,834
Marketing and advertising	346	688	1,348	2,133
Other operating expenses	3,833	10,922	14,171	20,760
Total operating expenses	142,334	139,598	472,960	388,362
Loss from operations	(69,826)	(59,496)	(226,679)	(155,485)
Other income (expense), net	15,074	6,333	37,508	(3,542)
Loss before income tax expense	(54,752)	(53,163)	(189,171)	(159,027)
Income tax expense (benefit)	238	5	(6,584)	(573)
Net loss	(54,990)	(53,168)	(182,587)	(158,454)
Other comprehensive income (loss), net of taxes:
Change in foreign currency translation adjustment	(200)	(89)	(81)	(289)
Net change in unrealized gain (loss) on short-term investments	(162)	(291)	5,480	(8,054)
Net other comprehensive (loss) income	(362)	(380)	5,399	(8,343)
Comprehensive loss	$ (55,352)	$ (53,548)	$ (177,188)	$ (166,797)
Net loss per share attributable to common stockholders, basic (in dollars per share)	$ (0.10)	$ (0.10)	$ (0.34)	$ (0.29)
Net loss per share attributable to common stockholders, diluted (in dollars per share)	$ (0.10)	$ (0.10)	$ (0.34)	$ (0.29)
Weighted-average shares used in computing net loss per share attributable to common stockholders - basic (in shares)	529,488,986	548,990,212	535,797,471	545,614,599
Weighted-average shares used in computing net loss per share attributable to common stockholders - diluted (in shares)	529,488,986	548,990,212	535,797,471	545,614,599