Stock-Based Compensation - Performance Based Restricted Stock Units (Details) - USD ($)	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Fair value assumptions:
Stock based compensation expenses	$ 934,847	$ 1,517,302
Restricted stock units - Performance based awards
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward]
Outstanding at beginning of period (in shares)	988,958	988,958
Outstanding at end of period (in shares)	988,958	988,958
Weighted Average Grant Date Fair Value
Outstanding at beginning of period (in dollars per share)	$ 4.48	$ 4.48
Outstanding at end of period (in dollars per share)	$ 4.48	$ 4.48
Fair value assumptions:
Stock based compensation expenses	$ 171,210	$ 398,388
Unrecognized stock-based compensation expense	$ 700,000
Unrecognized stock-based compensation expense, weighted average remaining term (in years)	2 years

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

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