ASSETS HELD FOR SALE, DIVESTITURES AND DISCONTINUED OPERATIONS Discontinued Operations and Disposal Groups (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Disposal Group, Including Discontinued Operation, Income Statement Disclosures [Abstract]
Lease operating expenses	$ 14,244	$ 13,824	$ 12,639	$ 16,285	$ 11,050	$ 11,020	$ 11,961	$ 8,371	$ 56,992	$ 42,402	$ 33,817
Production taxes	5,237	5,476	3,837	3,893	2,950	8,724	7,551	6,390	18,443	25,615	21,758
Transportation, gathering and processing expenses	3,567	3,938	1,308	1,338	1,331	1,208	818	1,235	10,151	4,592	5,152
Impairment of Natural Gas and Crude Oil Properties									0	433	929
Income (loss) from discontinued operations, net of tax	$ 0	$ 0	$ 0	$ 0	$ 47,782	$ (80)	$ 1,191	$ (719)	0	48,174	(1,190)
Supplemental Cash Flows Information
Capital expenditures									(604,668)	(628,592)	(394,948)
Change in accounts payable related to purchases of properties and equipment									(45,230)	39,667	33,328
Net Assets Related to Discontinued Operations [Member]
Disposal Group, Including Discontinued Operation, Income Statement Disclosures [Abstract]
Natural gas, NGL and crude oil sales									24,149	39,001
Sales from natural gas marketing									0	2,825
Commodity price risk management gain (loss), net									(1,085)	14
Well operations, pipeline income and other									48	922
Disposal Group, Discontinued Operations, Total revenue									23,112	42,762
Lease operating expenses									1,280	6,522
Production taxes									1,579	3,716
Transportation, gathering and processing expenses									3,536	5,283
Cost of natural gas marketing									0	2,673
Impairment of Natural Gas and Crude Oil Properties									433	954
Depreciation, depletion and amortization									9,128	13,894
Accretion of ARO and other, Discontinued Operations									4,170	8,235
(Gain) loss on sale of properties and equipment									(76,479)	1,700
Total costs, expenses and other									(56,353)	42,977
Disposal Group, Including Discontinued Operation, Interest Expense									(2,222)	(1,755)
Disposal Group, Including Discontinued Operation, Interest Income									194	10
Income (loss) from discontinued operations									77,437	(1,960)
Income taxes (expense) benefit									(29,263)	770
Income (loss) from discontinued operations, net of tax									$ 48,174	(1,190)
PDCM Divestiture [Member]
Supplemental Cash Flows Information
Capital expenditures										(17,253)	(45,277)
Change in accounts payable related to purchases of properties and equipment										$ (5,727)	$ (4,738)