Supplemental Quarterly Data (Unaudited) (Details) (USD $) In Thousands, unless otherwise specified	0 Months Ended		3 Months Ended								12 Months Ended	3 Months Ended								12 Months Ended
	Dec. 31, 2013		Dec. 31, 2014		Sep. 30, 2014		Jun. 30, 2014		Mar. 31, 2014		Dec. 31, 2014	Dec. 16, 2013		Sep. 30, 2013		Jun. 30, 2013		Mar. 31, 2013		Dec. 16, 2013	Dec. 31, 2012
Successor
Selected Quarterly Financial Data
Oil, natural gas and natural gas liquids sales	$ 50,324		$ 254,043		$ 350,863		$ 360,380		$ 333,116		$ 1,298,402
Electricity sales	1,444		8,561		11,300		10,192		9,969		40,022
Gains (losses) on oil and natural gas derivatives	(5,049)		55,891		44,990		(25,562)		3,465		78,784
Total revenues and other, net	47,118		323,232		409,416		347,261		351,380		1,431,289
Total expenses	52,892	[1]	488,741	[1]	225,834	[1]	240,116	[1]	244,156	[1]
(Gains) losses on sale of assets and other, net	10,208		64,151		49,011		4,257		3,367		120,786
Net income (loss)	(19,973)		(251,275)		115,165		79,008		79,698		22,596
Predecessor
Selected Quarterly Financial Data
Oil, natural gas and natural gas liquids sales												255,575		306,183		274,715		266,772		1,103,245	937,261
Electricity sales												6,844		10,046		9,513		7,589		33,992	29,940
Gains (losses) on oil and natural gas derivatives												(24,303)		(45,293)		35,622		(737)		(34,711)	64,620
Total revenues and other, net												239,827		273,014		322,338		276,123		1,111,302	1,041,126
Total expenses												254,305	[1]	202,647	[1]	201,331	[1]	198,239	[1]
(Gains) losses on sale of assets and other, net												0		0		0		(23)		(23)	(1,782)
Net income (loss)												$ (28,529)		$ 28,178		$ 61,364		$ 32,434		$ 93,447	$ 171,539

[1] Includes the following expenses: lease operating, transportation, marketing, general and administrative, exploration, depreciation, depletion and amortization, impairment of long-lived assets and taxes, other than income taxes.