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Stock-Based Compensation - Schedule of Weighted Average Assumptions Used in Black-Scholes Options Pricing Model (Details)
3 Months Ended
Mar. 31, 2020
Mar. 31, 2019
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]    
Expected dividend yield 0.00% 0.00%
Risk free interest rate 1.80% 2.50%
Expected stock price volatility 87.60% 75.50%
Expected term (years) 6 years 1 month 6 days 6 years 1 month 6 days
Employee Stock Purchase Plan    
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]    
Expected dividend yield 0.00%  
Risk free interest rate 1.60%  
Expected stock price volatility 107.90%  
Expected term (years) 4 months 24 days