Stock-Based Compensation - Share-based compensation expense (Details) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Total share-based compensation expense	$ 876,413	$ 614,583	$ 3,895,041	$ 2,425,919
Service based awards
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Total share-based compensation expense	1,098,737	614,583	3,069,722	2,425,919
Restricted stock awards - Service based awards
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Total share-based compensation expense		20,222		1,292,125
Restricted stock units - Service based awards
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Total share-based compensation expense	502,080	166,417	1,273,903	166,417
Stock option awards - Service based awards
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Total share-based compensation expense	596,657	$ 427,944	1,795,819	967,377
Performance based awards
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Total share-based compensation expense	(222,324)		825,319
Restricted stock units - Performance based awards
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Total share-based compensation expense	(332,389)		468,814
Change in share-based compensation expense	700,000		700,000
Stock option awards - Performance based awards
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Total share-based compensation expense	110,065		356,505	$ 51,000
Restricted stock awards
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Change in share-based compensation expense	$ 700,000		$ 700,000