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Summary of Significant Accounting Policies - Summary of Revenue Percentage Accounted by Purchasers (Details) - Customer Concentration Risk - Sales Revenue, Net
12 Months Ended
Dec. 31, 2019
Dec. 31, 2018
Dec. 31, 2017
Shell Trading (US) Company      
Concentration Risk [Line Items]      
Revenue percentage accounted by purchasers 55.00% 53.00% 62.00%
Lion Oil, Inc.      
Concentration Risk [Line Items]      
Revenue percentage accounted by purchasers 30.00% 22.00% 3.00%
Targa Pipeline Mid-Continent, LLC      
Concentration Risk [Line Items]      
Revenue percentage accounted by purchasers 8.00% 11.00% 13.00%