Accrued Liabilities - Schedule of Accrued Liabilities (Details) - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018
Payables and Accruals [Abstract]
Bonus payable	$ 1,135	$ 3,244
Payroll payable	78	773
Accrued interest – 11.25% Senior Notes	14,063	14,063
Accrued interest – other	540	104
Accrued well costs	25,671	9,026
Third party payments for joint interest expenditures	3,435	0
Accrued severance, property and franchise taxes	1,174	96
Accrued federal income tax	439	441
Current portion of operating lease liability	179	0
Other	305	381
Total accrued liabilities	$ 47,019	$ 28,128
Debt instrument interest rate (as a percent)	11.25%