The weighted average fair value per share of warrants issued and the assumptions used in the Black-Scholes Model during the years ended December 31, 2020, 2019, and 2018 are set forth in the table below. (Details) - Warrant [Member] - $ / shares	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Class of Warrant or Right [Line Items]
Weighted average exercise price	$ 1.19	$ 5.63	$ 5.16
Weighted average grant date fair value	$ 1.56	$ 3.00	$ 2.79
Risk-free interest rate	0.34%	2.52%	2.36%
Volatility	68.80%	60.80%	62.12%
Term (in years)	10 years	5 years	5 years
Dividend yield	0.00%	0.00%	0.00%