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Fair Value Measurements (Details Textual) - USD ($)
12 Months Ended
Dec. 31, 2019
Dec. 31, 2018
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]    
Fair value of notes payable $ 1,060,000,000.00 $ 968,900,000
Pipe and other equipment    
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]    
Impairment charge for equipments held in inventory $ 0