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Segment Information and Major Customers - Segment Information by Major Customers (Detail) - Sales [Member] - Customer Concentration Risk [Member]
12 Months Ended
Dec. 31, 2016
Targa Pipeline Mid-Continent [Member]  
Revenue, Major Customer [Line Items]  
Revenue by major customers 34.18%
Continuum Producer Services [Member]  
Revenue, Major Customer [Line Items]  
Revenue by major customers 11.87%
Plains All American Inc., Oil Purchasers [Member]  
Revenue, Major Customer [Line Items]  
Revenue by major customers 40.72%
Infinity Hydrocarbons, LLC. [Member]  
Revenue, Major Customer [Line Items]  
Revenue by major customers 15.18%