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Stock-Based Compensation - Summary of Fair Value of Employee Stock Purchase Plan Estimated Weighted-average Assumptions (Details) - Employee Stock Purchase Plan
3 Months Ended 6 Months Ended
Jun. 30, 2020
Jun. 30, 2020
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]    
Expected term in years 6 months 6 months
Expected volatility 100.10% 100.10%
Risk-free interest rate 0.20% 0.20%