Accrued Liabilities - Schedule of Accrued Liabilities (Details) - USD ($) $ in Thousands	Jun. 30, 2018	Jan. 31, 2018	Dec. 31, 2017
Debt Instrument [Line Items]
Bonus payable	$ 1,023		$ 2,250
Payroll payable	22		18
Accrued interest - other	75		1,015
Accrued rent	312		156
Accrued well costs	8,204		8,386
Third party payments for joint interest expenditures	5,778		0
Accrued severance, property and franchise taxes	1,294		115
Accrued federal income tax	442		1,147
Other	541		728
Total accrued liabilities	31,519		16,583
8.750% Senior Notes Due April 15, 2019
Debt Instrument [Line Items]
Accrued interest - Senior Notes	$ 0		$ 2,768
Debt instrument interest rate	8.75%	8.75%	8.75%
11.25% Senior Notes
Debt Instrument [Line Items]
Accrued interest - Senior Notes	$ 13,828		$ 0
Debt instrument interest rate	11.25%	11.25%	11.25%