CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Revenues
Gain on sales of assets, net	$ 16	$ 4	$ 41	$ 79
Total revenues	122,767	111,580	227,995	188,791
Operating expenses
Lease operating	10,362	8,730	21,366	16,026
Gathering, processing and transportation	6,408	4,574	10,337	7,933
Production and ad valorem taxes	7,579	5,795	13,271	9,887
General and administrative	6,232	5,322	13,297	11,793
Depreciation, depletion and amortization	44,298	31,273	83,168	53,354
Total operating expenses	74,879	55,694	141,439	98,993
Operating income (loss)	47,888	55,886	86,556	89,798
Other income (expense)
Interest expense	(9,056)	(6,150)	(18,534)	(10,751)
Derivatives	13,603	(52,241)	(54,414)	(71,036)
Other, net	8	(16)	114	(74)
Income (loss) before income taxes	52,443	(2,521)	13,722	7,937
Income tax benefit (expense)	(818)	0	(794)	(163)
Net income (loss) attributable to common shareholders	$ 51,625	$ (2,521)	$ 12,928	$ 7,774
Net income (loss) per share:
Basic (in dollars per share)	$ 3.42	$ (0.17)	$ 0.86	$ 0.52
Diluted (in dollars per share)	$ 3.40	$ (0.17)	$ 0.85	$ 0.51
Weighted average shares outstanding – basic (in shares)	15,106	15,058	15,102	15,050
Weighted average shares outstanding – diluted (in shares)	15,162	15,058	15,174	15,171
Oil and Gas, Exploration and Production [Member]
Revenues
Revenues	$ (114,031)	$ (101,716)	$ (208,843)	$ (172,974)
Oil and Condensate [Member]
Revenues
Revenues	(3,502)	(5,533)	(9,050)	(8,479)
Natural Gas, Production [Member]
Revenues
Revenues	(5,290)	(3,912)	(9,567)	(6,702)
Product and Service, Other [Member]
Revenues
Revenues	$ (72)	$ (415)	$ (494)	$ (557)