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CONCENTRATIONS (Tables)
 12 Months Ended
Dec. 31, 2015
Risks and Uncertainties [Abstract]  
Customers from Whom We Derived 10% or More of Total Oil and Gas Revenue
The following table identifies customers from whom we derived 10% or more of our total oil and natural gas revenue during the indicated periods:
 
Year Ended December 31,
 
2015
 
2014
 
2013
Phillips 66 Company
53
%
 
31
%
 
35
%
Shell Trading (US) Company
13
%
 
32
%
 
33
%