Stock-Based Compensation - Service Based Stock Options - Others (Details) - USD ($)	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Payment Arrangement, Expense	$ 4,951,820	$ 4,387,554
Stock option awards - Service based awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted (in shares)	1,103,938	1,447,479
Vested options, exercisable (in shares)	6,481,095
Vested options exercisable at an average price	$ 7.97
Unvested options exercisable at an average price	$ 3.66
Share-based Payment Arrangement, Expense	$ 2,300,323	$ 1,588,291
Unrecognized stock-based compensation expenses	$ 2,200,000
Stock option awards - Service based awards \| Chief Executive Officer
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Accelerated vesting		258,334
Stock option awards - Service based awards \| Chief Financial Officer
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Accelerated vesting		71,667
Additional stock-based compensation		$ 162,000

Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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