Consolidated Statements of Income (USD $) In Thousands, except Per Share data, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Revenues
Contract drilling	$ 529,719	$ 484,651	$ 316,384
Oil and natural gas	567,944	514,614	399,771
Gas gathering and processing	217,460	208,238	154,516
Total revenues	1,315,123	1,207,503	870,671
Contract drilling
Operating costs	289,524	269,899	186,813
Depreciation	81,007	79,667	69,970
Oil and natural gas
Operating costs	150,212	131,271	105,365
Depreciation, depletion and amortization	211,347	183,350	118,793
Impairment of oil and natural gas properties (Note 2)	283,606	0	0
Gas gathering and processing
Operating costs	187,292	174,859	122,146
Depreciation, amortization, and impairment	24,388	16,101	15,385
General and administrative	33,086	30,055	26,152
Total expenses	1,260,462	885,202	644,624
Income from operations	54,661	322,301	226,047
Other income (expense)
Interest, net	(14,137)	(4,167)	0
Gain (loss) on derivatives not desgignated as hedges and hedge ineffectiveness, net	(1,243)	1,702	1,036
Other	121	(834)	10,138
Total other income (expense)	(15,259)	(3,299)	11,174
Income before income taxes	39,402	319,002	237,221
Income tax expense (benefit)
Current	696	(2,416)	(9,935)
Deferred	15,530	125,551	100,672
Total income taxes	16,226	123,135	90,737
Net income	$ 23,176	$ 195,867	$ 146,484
Net income per common share:
Basic	$ 0.48	$ 4.11	$ 3.10
Diluted	$ 0.48	$ 4.08	$ 3.09