CONDENSED CONSOLIDATED STATEMENT OF INCOME (Unaudited) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended
	Mar. 31, 2014	Mar. 31, 2013
Operating revenue:
Oil production	$ 138,289	$ 186,925
Gas production	56,362	36,822
Natural gas liquids production	27,970	9,178
Other operational income	1,209	807
Total operating revenue	223,830	233,732
Operating expenses:
Lease operating expenses	46,903	53,044
Transportation, processing and gathering expenses	14,626	5,397
Production taxes	3,062	2,089
Depreciation, depletion and amortization	82,646	75,435
Accretion expense	7,555	8,263
Salaries, general and administrative expenses	16,329	13,952
Incentive compensation expense	3,134	1,431
Other operational expenses	424	72
Derivative expense, net	599	1,221
Total operating expenses	175,278	160,904
Income from operations	48,552	72,828
Other (income) expenses:
Interest expense	8,357	9,635
Interest income	(143)	(117)
Other income	(707)	(726)
Total other (income) expenses	7,507	8,792
Income before income taxes	41,045	64,036
Provision (benefit) for income taxes:
Current		(3,746)
Deferred	15,102	27,024
Total income taxes	15,102	23,278
Net income	$ 25,943	$ 40,758
Basic earnings per share	$ 0.52	$ 0.82
Diluted earnings per share	$ 0.52	$ 0.82
Average shares outstanding	49,013	48,619
Average shares outstanding assuming dilution	49,062	48,657