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Summary of Significant Accounting Policies - Schedule of Weighted-Average Assumptions (Details)
12 Months Ended
Dec. 31, 2019
Dec. 31, 2018
Dec. 31, 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Expected dividend yield 0.00%    
Stock options      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Expected common stock price volatility 110.00% 85.00% 81.00%
Risk-free interest rate, minimum 1.38% 2.39% 1.82%
Risk-free interest rate, maximum 2.54% 2.95% 2.38%
Expected term of options (years) 4 years 9 months 6 days 6 years 6 days 6 years 1 month 6 days
Expected dividend yield 0.00% 0.00% 0.00%