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Stockholders' Equity (Deficit) - Schedule of Assumptions Used to Estimate Fair Value of Stock Option Grants (Details)
12 Months Ended
Dec. 31, 2019
Dec. 31, 2018
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]    
Risk-free interest rate 1.60% 2.90%
Expected volatility 77.60% 64.70%
Expected term (in years) 6 years 6 years 1 month 6 days