Stock-Based Compensation - Summary of Stock-based Compensation (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Stock-Based Compensation expense	$ 7,768	$ 29,686	$ 14,144	$ 46,777
Platform Operations
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Stock-Based Compensation expense	1,303	5,540	2,389	8,701
Sales and Marketing
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Stock-Based Compensation expense	2,426	11,914	4,605	18,727
Technology and Development
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Stock-Based Compensation expense	1,425	5,029	2,594	7,968
General and Administrative
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Stock-Based Compensation expense	$ 2,614	$ 7,203	$ 4,556	$ 11,381