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Share-Based Compensation - Schedule of Weighted Average Assumptions to Estimate Grant Date Fair Value (Details) - Performance Stock Units [Member] - $ / shares
12 Months Ended
Dec. 31, 2020
Dec. 31, 2019
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]    
Stock price $ 2.24 $ 9.05
Volatility 53.40% 42.30%
Risk-free rate 0.60% 2.42%
Dividend yield 9.10% 8.84%
Derived service period 3 years  
Minimum [Member]    
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]    
Derived service period   2 years 4 months 6 days
Maximum [Member]    
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]    
Derived service period   4 years