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Oil and Natural Gas Properties (Details) - USD ($)
3 Months Ended
Mar. 31, 2018
Mar. 31, 2017
Oil And Natural Gas Properties [Line Items]    
Impairment of proved and unproved oil and gas properties $ 0 $ 0
Proved Oil and Natural Gas Properties    
Oil And Natural Gas Properties [Line Items]    
Depletion expenses $ 9,600,000 $ 7,800,000
Unproved Oil and Gas Properties | Minimum    
Oil And Natural Gas Properties [Line Items]    
Unproved oil and gas lease term 3 years  
Unproved Oil and Gas Properties | Maximum    
Oil And Natural Gas Properties [Line Items]    
Unproved oil and gas lease term 5 years