Stock-Based Compensation - Summary of Stock-based Compensation (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Stock-Based Compensation expense	$ 6,376	$ 17,090
Platform Operations
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Stock-Based Compensation expense	1,086	3,161
Sales and Marketing
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Stock-Based Compensation expense	2,179	6,813
Technology and Development
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Stock-Based Compensation expense	1,169	2,939
General and Administrative
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Stock-Based Compensation expense	$ 1,942	$ 4,177