Income Taxes (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Deferred tax assets:
Net operating loss carry forwards	$ 39,976	$ 35,044
Other	2,520	2,203
Total gross deferred tax assets	42,496	37,247
Less - valuation allowance	(40,825)	(32,750)
Net deferred tax assets	1,671	4,497
Deferred tax liabilities:
Property and equipment	8	9
Other	(269)	50
Unproved oil and gas properties	(1,410)	(4,556)
Total gross deferred tax liabilities	(1,671)	(4,497)
Net deferred tax asset