SUBSIDIARY GUARANTOR SUBSIDIARY GUARANTOR INCOME STATEMENT (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Revenues [Abstract]
Crude oil, natural gas, and NGLs sales									$ 913,084	$ 497,353	$ 378,713
Commodity price risk management gain (loss), net									(3,936)	(125,681)	203,183
Other income									12,468	11,243	13,430
Total revenues	$ 189,516	$ 183,235	$ 275,158	$ 273,707	$ 108,097	$ 163,890	$ 20,097	$ 90,831	921,616	382,915	595,326
Costs and Expenses [Abstract]
Lease operating expenses									89,641	59,950	56,992
Production taxes									60,717	31,410	18,443
Transportation, gathering, and processing expenses									33,220	18,415	10,151
Exploration, geologic, and geophysical expense									47,334	4,669	1,102
Impairment of properties and equipment									285,887	9,973	161,620
Impairment of goodwill									75,121	0	0
General and administrative expense									120,370	112,470	89,959
Depreciation, depletion and amortization									469,084	416,874	303,258
Provision for uncollectible notes receivable									(40,203)	44,038	0
Accretion of asset retirement obligations									6,306	7,080	6,293
Gain on sale of properties and equipment									(766)	(43)
Other expenses									13,157	10,193	11,717
Total costs, expenses and other	208,016	579,326	190,522	182,004	178,608	179,178	163,379	193,864	1,159,868	715,029	659,150
Income (loss) from operations	(18,500)	(396,091)	84,636	91,703	(70,511)	(15,288)	(143,282)	(103,033)	(238,252)	(332,114)	(63,824)
Loss on extinguishment of debt									(24,747)	0	0
Interest expense									(78,694)	(61,972)	(47,571)
Interest income									2,261	963	4,807
Income (loss) before income taxes	(62,808)	(414,887)	65,787	72,476	(90,636)	(35,341)	(153,777)	(113,369)	(339,432)	(393,123)	(106,588)
Income tax benefit									211,928	147,195	38,308
Equity in loss of subsidiary									0	0
Net income (loss)	$ 77,637	$ (292,537)	$ 41,250	$ 46,146	$ (55,639)	$ (23,309)	$ (95,450)	$ (71,530)	(127,504)	(245,928)	$ (68,280)
Parent [Member]
Revenues [Abstract]
Crude oil, natural gas, and NGLs sales									788,400	491,750
Commodity price risk management gain (loss), net									(3,936)	(125,681)
Other income									11,901	11,241
Total revenues									796,365	377,310
Costs and Expenses [Abstract]
Lease operating expenses									68,031	58,401
Production taxes									53,236	31,132
Transportation, gathering, and processing expenses									23,301	18,263
Exploration, geologic, and geophysical expense									1,092	1,197
Impairment of properties and equipment									4,951	9,973
Impairment of goodwill									0
General and administrative expense									107,518	112,166
Depreciation, depletion and amortization									403,984	415,321
Provision for uncollectible notes receivable									(40,203)	44,038
Accretion of asset retirement obligations									5,965	7,070
Gain on sale of properties and equipment									(766)	(43)
Other expenses									13,157	10,193
Total costs, expenses and other									640,266	707,711
Income (loss) from operations									156,099	(330,401)
Loss on extinguishment of debt									(24,747)
Interest expense									(79,919)	(62,002)
Interest income									2,261	963
Income (loss) before income taxes									53,694	(391,440)
Income tax benefit									(33,643)	147,195
Equity in loss of subsidiary									(147,555)	(1,683)
Net income (loss)									(127,504)	(245,928)
Guarantor Subsidiaries [Member]
Revenues [Abstract]
Crude oil, natural gas, and NGLs sales									124,684	5,603
Commodity price risk management gain (loss), net									0	0
Other income									567	2
Total revenues									125,251	5,605
Costs and Expenses [Abstract]
Lease operating expenses									21,610	1,549
Production taxes									7,481	278
Transportation, gathering, and processing expenses									9,919	152
Exploration, geologic, and geophysical expense									46,242	3,472
Impairment of properties and equipment									280,936	0
Impairment of goodwill									75,121
General and administrative expense									12,852	304
Depreciation, depletion and amortization									65,100	1,553
Provision for uncollectible notes receivable									0	0
Accretion of asset retirement obligations									341	10
Gain on sale of properties and equipment									0	0
Other expenses									0	0
Total costs, expenses and other									519,602	7,318
Income (loss) from operations									(394,351)	(1,713)
Loss on extinguishment of debt									0
Interest expense									1,225	30
Interest income									0	0
Income (loss) before income taxes									(393,126)	(1,683)
Income tax benefit									245,571	0
Equity in loss of subsidiary									0	0
Net income (loss)									(147,555)	(1,683)
Consolidation, Eliminations [Member]
Revenues [Abstract]
Crude oil, natural gas, and NGLs sales									0	0
Commodity price risk management gain (loss), net									0	0
Other income									0	0
Total revenues									0	0
Costs and Expenses [Abstract]
Lease operating expenses									0	0
Production taxes									0	0
Transportation, gathering, and processing expenses									0	0
Exploration, geologic, and geophysical expense									0	0
Impairment of properties and equipment									0	0
Impairment of goodwill									0
General and administrative expense									0	0
Depreciation, depletion and amortization									0	0
Provision for uncollectible notes receivable									0	0
Accretion of asset retirement obligations									0	0
Gain on sale of properties and equipment									0	0
Other expenses									0	0
Total costs, expenses and other									0	0
Income (loss) from operations									0	0
Loss on extinguishment of debt									0
Interest expense									0	0
Interest income									0	0
Income (loss) before income taxes									0	0
Income tax benefit									0	0
Equity in loss of subsidiary									147,555	1,683
Net income (loss)									$ 147,555	$ 1,683