Stock-Based Compensation - Stock-based Compensation Expense (Details) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Stock-based compensation expense	$ 2,432,670	$ 12,735,549	$ 6,354,546	$ 16,141,039
Cost of Revenues [Member]
Stock-based compensation expense	85,784	522,377	237,273	687,129
General and administrative expense
Stock-based compensation expense	1,514,678	7,432,609	4,032,315	9,716,732
Selling and Marketing Expense [Member]
Stock-based compensation expense	628,076	3,803,687	1,597,723	4,586,015
Engineering And Development [Member]
Stock-based compensation expense	$ 204,132	$ 976,876	$ 487,235	$ 1,151,163