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Oil and Gas Properties - Additional Information (Details)
$ in Thousands
3 Months Ended 6 Months Ended
Jun. 30, 2017
USD ($)
a
Jun. 30, 2016
USD ($)
Jun. 30, 2017
USD ($)
a
Jun. 30, 2016
USD ($)
Oil And Gas Exploration And Production Industries Disclosures [Abstract]        
Impairment of oil and gas properties | $ $ 27,081 $ 1,938 $ 27,081 $ 1,938
Area of land development | a 57,172   57,172