Unaudited Condensed Consolidated Statements Of Operations - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Revenues
Revenues	$ 53,145	$ 58,737	$ 146,101	$ 143,281
Expenses
Lease operating and gas gathering	10,055	6,687	26,695	17,761
Production and ad valorem taxes	3,017	3,218	8,126	8,145
Depreciation, depletion and amortization	24,635	23,775	64,120	59,937
Loss on sale of oil and gas properties	483	0	33,530	1,568
Impairment of oil and gas properties	0	12,169	0	12,169
General and administrative	4,124	4,661	12,345	13,385
Acquisition costs and other	(2)	315	(4)	302
Total expenses	42,312	50,825	144,812	113,267
Income from operations	10,833	7,912	1,289	30,014
Other expense
Interest expense	(11,295)	(10,215)	(32,730)	(28,771)
Change in fair value of warrants	(100)	509	594	(2,105)
Gain (loss) on derivative financial instruments	21,546	(18,198)	(5,177)	(54,852)
Loss on extinguishment of debt	0	0	0	(8,619)
Total other expense	10,151	(27,904)	(37,313)	(94,347)
Income (loss) before income taxes	20,984	(19,992)	(36,024)	(64,333)
Income tax (expense) benefit	(4,767)	282	6,966	6,493
Net income (loss)	16,217	(19,710)	(29,058)	(57,840)
Preferred stock dividends	(2,159)	(1,975)	(6,336)	(5,796)
Net income (loss) attributable to common stockholders	$ 14,058	$ (21,685)	$ (35,394)	$ (63,636)
Net income (loss) per common share
Basic (in dollars per share)	$ 0.34	$ (0.88)	$ (1.42)	$ (2.59)
Diluted (in dollars per share)	$ 0.33	$ (0.88)	$ (1.42)	$ (2.59)
Weighted average common shares outstanding
Basic (in shares)	24,933,853	24,599,744	24,852,994	24,598,816
Diluted (in shares)	25,331,810	24,599,744	24,852,994	24,598,816
Oil sales
Revenues
Revenues	$ 42,187	$ 47,846	$ 120,496	$ 120,705
Natural gas liquid sales
Revenues
Revenues	3,439	6,795	10,381	12,939
Natural gas sales
Revenues
Revenues	$ 7,519	$ 4,096	$ 15,224	$ 9,637