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Stock Compensation and Unit-Based Compensation - Summary of Weighted Average Assumptions Used in Valuing Plans (Details) - $ / shares
12 Months Ended
Dec. 31, 2019
Dec. 31, 2018
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]    
Fair value at grant date $ 3.39 $ 2.50
Expected volatility 95.90% 70.90%
Risk-free interest rate 2.10% 2.70%
Expected holding period, in years 5 years 10 months 24 days 5 years 10 months 24 days
2019 Employee Stock Purchase Plan    
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]    
Fair value at grant date $ 0.75  
Expected volatility 169.00%  
Risk-free interest rate 2.30%  
Expected holding period, in years 6 months