Unaudited Consolidated Statements Of Operations - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Revenues
Revenues	$ 52,215	$ 47,852	$ 92,956	$ 84,544
Expenses
Lease operating and gas gathering	8,929	6,490	16,638	11,074
Production and ad valorem taxes	2,818	2,761	5,109	4,927
Depreciation, depletion and amortization	21,515	20,737	39,486	36,162
Loss on sale of oil and gas properties	155	0	33,046	1,568
General and administrative	3,841	5,305	8,221	8,724
Acquisition costs and other	0	(3)	(2)	(13)
Total expenses	37,258	35,290	102,498	62,442
Income (loss) from operations	14,957	12,562	(9,542)	22,102
Other expense
Interest expense	(10,778)	(9,298)	(21,434)	(18,555)
Change in fair value of warrants	796	(2,462)	694	(2,615)
Gain (loss) on derivative financial instruments	9,514	(25,498)	(26,724)	(36,654)
Loss on extinguishment of debt	0	0	0	(8,619)
Total other expense	(468)	(37,258)	(47,464)	(66,443)
Income (loss) before income taxes	14,489	(24,696)	(57,006)	(44,341)
Income tax (expense) benefit	(1,200)	3,103	11,732	6,211
Net income (loss)	13,289	(21,593)	(45,274)	(38,130)
Preferred stock dividends	(2,112)	(1,932)	(4,177)	(3,821)
Net income (loss) attributable to common stockholders	$ 11,177	$ (23,525)	$ (49,451)	$ (41,951)
Net income (loss) per common share
Basic (in dollars per share)	$ 0.28	$ (0.96)	$ (1.99)	$ (1.71)
Diluted (in dollars per share)	$ 0.28	$ (0.96)	$ (1.99)	$ (1.71)
Weighted average common shares outstanding
Basic (in shares)	24,924,169	24,599,744	24,811,895	24,598,345
Diluted (in shares)	24,924,169	24,599,744	24,811,895	24,598,345
Oil sales
Revenues
Revenues	$ 44,726	$ 39,707	$ 78,310	$ 72,859
Natural gas liquid sales
Revenues
Revenues	3,549	4,410	6,942	6,143
Natural gas sales
Revenues
Revenues	$ 3,940	$ 3,735	$ 7,704	$ 5,542