Stock-Based Compensation - Service Based Restricted Stock Units (Details) - USD ($)	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Weighted Average Grant Date Fair Value
Stock based compensation expenses	$ 934,847	$ 1,517,302
Restricted stock units - Service 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)	463,786	472,959
Granted (in shares)	16,304
Forfeited (in shares)	(7,460)
Outstanding at end of period (in shares)	472,630	472,959
Weighted Average Grant Date Fair Value
Outstanding at beginning of period (in dollars per share)	$ 4.26	$ 4.32
Granted (in dollars per share)	2.61
Forfeited (in dollars per share)	4.15
Outstanding at end of period (in dollars per share)	$ 4.21	$ 4.32
Stock based compensation expenses	$ 200,000	$ 300,000
Unrecognized stock-based compensation expense	$ 700,000
Unrecognized stock-based compensation expense, weighted average remaining term (in years)	1 year
Minimum \| Restricted stock units - Service based awards
Weighted Average Grant Date Fair Value
Vesting period	1 year
Maximum \| Restricted stock units - Service based awards
Weighted Average Grant Date Fair Value
Vesting period	3 years

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

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Weighted average fair value as of the grant date of equity-based award plans other than stock (unit) option plans that were not exercised or put into effect as a result of the occurrence of a terminating event.

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Per share or unit weighted-average fair value of nonvested award under share-based payment arrangement. Excludes share and unit options.

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