CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY - USD ($) $ in Thousands	Total	Common Stock [Member]	Additional Paid in Capital [Member]	Accumulated Deficit [Member]
Balance at Dec. 31, 2014	$ 207,495	$ 1,062	$ 309,773	$ (103,340)
Balance (in shares) at Dec. 31, 2014		106,186,678
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)	(127,110)		0	(127,110)
Stock issued for acquisition of oil and gas properties	0
Stock-based compensation	3,912		3,912	0
Stock options exercised	168	$ 1	167	0
Stock options exercised (in shares)		164,400
Restricted stock issued, net of cancellations	0	$ 0	0	0
Restricted stock issued, net of cancellations (in shares)		(5,077)
Balance at Dec. 31, 2015	84,465	$ 1,063	313,852	(230,450)
Balance (in shares) at Dec. 31, 2015		106,346,001
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)	(96,378)	$ 0	0
Stock issuance	27,135	$ 287	26,848	0
Stock issuance (in shares)		28,750,000
Stock issued for acquisition of oil and gas properties	0
Stock issued for compensation	40		40	0
Stock issued for compensation (in shares)		41,102
Stock-based compensation	3,194	$ 0	3,194	0
Stock options exercised	49	$ 1	48	0
Stock options exercised (in shares)		55,716
Restricted stock issued, net of cancellations	0	$ 0	0	0
Restricted stock issued, net of cancellations (in shares)		(98,802)
Balance at Dec. 31, 2016	$ 18,505	$ 1,351	343,982	(326,828)
Balance (in shares) at Dec. 31, 2016	135,094,017	135,094,017
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)	$ 16,006		0
Stock issuance	65,224	$ 288	64,936	0
Stock issuance (in shares)		28,750,000
Stock issued for acquisition of oil and gas properties	3,335	$ 20	3,315	0
Stock issued for acquisition of oil and gas properties (in shares)		2,000,000
Stock-based compensation	3,238		3,238	0
Stock options exercised	0	$ 0	0	0
Stock options exercised (in shares)		2,634
Restricted stock issued, net of cancellations	0	$ 0	0	0
Restricted stock issued, net of cancellations (in shares)		43,250
Balance at Dec. 31, 2017	$ 106,308	$ 1,659	$ 415,471	$ (310,822)
Balance (in shares) at Dec. 31, 2017	165,889,901	165,889,901