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Stock-Based Compensation - Schedule of Fair Value Assumptions of Stock Options (Details)
3 Months Ended
Mar. 31, 2021
Mar. 31, 2020
Share-based Payment Arrangement [Abstract]    
Risk-free interest rate 0.78% 1.51%
Expected life 6 years 6 years
Expected volatility 134.79% 128.87%
Dividend yield 0.00% 0.00%