Supplemental Disclosures (Details 1) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Supplemental disclosures of cash flow information
Cash paid for interest expense, net of amounts capitalized	$ 0	$ 1,990
Asset retirement obligations related to mineral properties	1,606	1,507
Asset retirement obligations related to support equipment and facilities	(65)	32
(Decrease) increase in liabilities for oil and natural gas properties capital expenditures	(11,622)	8,654
(Decrease) increase in liabilities for support equipment and facilities	(5,000)	6,865
Increase in liabilities for accrued cost to issue equity	216	0
Issuance of restricted stock units for Board and advisor services	138	142
Issuance of common stock for advisor services	0	4
Stock-based compensation expense recognized as liability	(98)	263
Transfer of inventory from oil and natural gas properties	$ 64	$ 310