Accrued Liabilities - Schedule of Accrued Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Payables And Accruals [Abstract]
Bonus payable	$ 2,250	$ 2,155
Payroll payable	18	1
Accrued interest - 8.750% Senior Notes	2,768	2,924
Accrued interest - other	1,015	523
Accrued rent	156	298
Accrued well costs	8,386	3,366
Accrued severance, property, federal and franchise taxes	115	431
Accrued federal income tax	1,147
Other	728	249
Total accrued liabilities	$ 16,583	$ 9,947