CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Revenues
Gain on sales of assets, net	$ 77	$ 2	$ 118	$ 81
Total revenues	119,304	127,185	347,299	315,976
Operating expenses
Lease operating	11,868	9,898	33,234	25,924
Gathering, processing and transportation	6,600	4,928	16,937	12,861
Production and ad valorem taxes	7,401	7,152	20,672	17,039
General and administrative	6,876	6,155	20,173	17,948
Depreciation, depletion and amortization	46,519	35,016	129,687	88,370
Total operating expenses	79,264	63,149	220,703	162,142
Operating income (loss)	40,040	64,036	126,596	153,834
Other income (expense)
Interest expense	(8,736)	(7,322)	(27,270)	(18,073)
Derivatives	24,248	(40,689)	(30,166)	(111,725)
Other, net	(248)	241	(134)	167
Income (loss) before income taxes	55,304	16,266	69,026	24,203
Income tax benefit (expense)	(942)	10	(1,736)	(153)
Net income (loss) attributable to common shareholders	$ 54,362	$ 16,276	$ 67,290	$ 24,050
Net income (loss) per share:
Basic (in dollars per share)	$ 3.60	$ 1.08	$ 4.45	$ 1.60
Diluted (in dollars per share)	$ 3.59	$ 1.06	$ 4.44	$ 1.57
Weighted average shares outstanding – basic (in shares)	15,110	15,062	15,105	15,054
Weighted average shares outstanding – diluted (in shares)	15,160	15,344	15,165	15,278
Oil and Gas, Exploration and Production [Member]
Revenues
Revenues	$ (110,618)	$ (117,059)	$ (319,461)	$ (290,033)
Oil and Condensate [Member]
Revenues
Revenues	(3,546)	(5,976)	(12,596)	(14,455)
Natural Gas, Production [Member]
Revenues
Revenues	(4,215)	(3,768)	(13,782)	(10,470)
Product and Service, Other [Member]
Revenues
Revenues	$ 848	$ (380)	$ (1,342)	$ (937)