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Stock-Based Compensation - Schedule of Estimated Fair Value of Options Valuation Assumptions (Details) - $ / shares
6 Months Ended
Jun. 30, 2020
Jun. 30, 2019
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]    
Risk-free interest rate, minimum 0.41% 1.85%
Risk-free interest rate, maximum 1.71% 2.51%
Expected dividend yield 0.00% 0.00%
Expected volatility, minimum 72.00% 73.00%
Expected volatility, maximum 75.00% 74.00%
Weighted-average grant date fair value $ 4.06 $ 2.14
Minimum    
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]    
Expected life 5 years 6 months 5 years 6 months
Maximum    
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]    
Expected life 6 years 7 months 6 days 6 years