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Stock-Based Compensation Plan (Details) - 2017 Stock Option Plan
3 Months Ended 12 Months Ended
Mar. 31, 2021
Dec. 31, 2020
Fair value assumptions    
Expected term (in years)   5 years
Stock option    
Fair value assumptions    
Expected volatility 80.00% 81.00%
Expected dividend yield 0.00%  
Risk-free interest rate   0.37%