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Stock-Based Compensation - Schedule of Assumptions Used in Estimation of Fair Value of the Share-based Payment Awards on the Grant Date (Details) - Options
3 Months Ended
Mar. 31, 2018
Mar. 31, 2017
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]    
Risk-free interest rate 2.20% 1.60%
Volatility 109.50% 70.20%
Expected life (years) 4 years 4 years
Dividend yield   0.00%