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Stockholders' Equity - Schedule of Stock Option Valuation Assumptions (Details)
6 Months Ended
Jun. 30, 2020
Jun. 30, 2019
Stockholders’ Equity    
Dividend yield 0.00%  
Expected volatility 89.61% 131.10%
Risk-free interest rate 0.86% 2.50%
Expected lives (years) 5 years 10 months 24 days 5 years 6 months