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Stock-Based Compensation - Schedule of Assumptions Used to Determine Fair Value of Options Granted (Details)
12 Months Ended
Dec. 31, 2019
Dec. 31, 2018
Risk-free interest rate, minimum 2.82% 2.82%
Risk-free interest rate, maximum 3.02% 3.02%
Expected volatility, minimum 101.30% 99.90%
Expected volatility, maximum 106.20% 102.10%
Expected dividend yield 0.00% 0.00%
Minimum [Member]    
Expected life (in years) 7 years 6 months 8 years 6 months
Maximum [Member]    
Expected life (in years) 9 years 3 months 19 days 10 years