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Share-Based Compensation (Tables)
3 Months Ended
Mar. 31, 2021
Share-based Payment Arrangement [Abstract]  
Schedule of Valuation Assumptions
The ranges for the assumptions used in the Monte Carlo model for the PRSUs granted during 2021, 2020 and 2019 are presented as follows:
202120202019
Expected volatility126.2 %
101.32% to 117.71%
49.9 %
Dividend yield0.0 %0.0 %0.0 %
Risk-free interest rate0.22 %
0.18% to 0.51%
1.66 %