Consolidated Statements of Stockholders' Equity - USD ($) $ in Thousands	Common Stock [Member]	Additional Paid-in Capital [Member]	Retained Earnings [Member]	Total
Balance (in shares) at Dec. 31, 2015	106,346,001
Balance at Dec. 31, 2015	$ 1,063	$ 313,852	$ (230,450)	$ 84,465
Net (loss) income			(96,378)	(96,378)
Stock issuance (in shares)	28,750,000
Stock issuance	$ 287	26,848		27,135
Stock issued for compensation (in shares)	41,102
Stock issued for compensation		40		40
Stock-based compensation		3,194		3,194
Stock options exercised (in shares)	55,716
Stock options exercised	$ 1	48		49
Restricted stock issued, net of forfeitures (in shares)	(98,802)
Restricted stock issued, net of forfeitures
Balance (in shares) at Dec. 31, 2016	135,094,017
Balance at Dec. 31, 2016	$ 1,351	343,982	(326,828)	18,505
Net (loss) income			16,006	16,006
Stock issuance (in shares)	28,750,000
Stock issuance	$ 288	64,936		65,224
Stock-based compensation		3,238		3,238
Stock options exercised (in shares)	2,634
Stock options exercised
Restricted stock issued, net of forfeitures (in shares)	43,250
Restricted stock issued, net of forfeitures
Stock issued for acquisition of oil and gas properties (in shares)	2,000,000
Stock issued for acquisition of oil and gas properties	$ 20	3,315		$ 3,335
Balance (in shares) at Dec. 31, 2017	165,889,901			165,889,901
Balance at Dec. 31, 2017	$ 1,659	415,471	(310,822)	$ 106,308
Net (loss) income			57,821	57,821
Stock-based compensation		2,366		2,366
Stock options exercised (in shares)	150,327
Stock options exercised	$ 1	13		14
Restricted stock issued, net of forfeitures (in shares)	673,556
Restricted stock issued, net of forfeitures	$ 7	(6)		$ 1
Balance (in shares) at Dec. 31, 2018	166,713,784			166,713,784
Balance at Dec. 31, 2018	$ 1,667	$ 417,844	$ (253,001)	$ 166,510