QUARTERLY DATA (UNAUDITED) (Schedule of Quarterly Data) (Details) - USD ($) $ / shares in Units, $ in Thousands	1 Months Ended	2 Months Ended	3 Months Ended							5 Months Ended	6 Months Ended	7 Months Ended	12 Months Ended
	Jun. 30, 2018	May 31, 2018	Dec. 31, 2018	Sep. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	May 31, 2018	Dec. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Revenues	$ 21,720		$ 47,914	$ 68,966								$ 138,600
Gross profit	11,246		18,427	37,319
Net income (loss)	$ (538)		$ 34,267	$ (9,760)								$ 23,969
Net income (loss) per share/unit:
Basic, share/unit	$ (0.05)		$ 3.41	$ (0.97)								$ 2.39
Diluted, share/unit	$ (0.05)		$ 3.41	$ (0.97)								$ 2.39
Revenue excluding royalty			$ 52,900									$ 143,600
Reorganization items, net												2,323
Impairment of oil and gas properties												3,065
Proved oil and natural gas properties
Net income (loss) per share/unit:
Impairment of oil and gas properties												3,100
Predecessor
Revenues		$ 43,089			$ 67,942	$ 60,003	$ 52,651	$ 56,052	$ 56,987	$ 111,031			$ 225,693	$ 184,894
Gross profit		23,201			36,558	32,119	23,026	26,861	29,809
Net income (loss)		$ (595,076)			$ (15,449)	$ (40,321)	$ (17,888)	$ (25,161)	$ (50,831)	$ (610,525)			$ (134,201)	$ (242,895)
Net income (loss) per share/unit:
Basic, share/unit		$ (11.81)			$ (0.31)					$ (12.12)			$ (2.66)	$ (4.85)
Diluted, share/unit		$ (11.81)			$ (0.31)					$ (12.12)			$ (2.66)	$ (4.85)
Basic, unit						$ (0.80)	$ (0.36)	$ (0.50)	$ (1.01)
Diluted, unit						$ (0.80)	$ (0.36)	$ (0.50)	$ (1.01)
Reorganization items, net										$ 587,325
Impairment of oil and gas properties										3	$ 93,600		$ 93,607	$ 131,260
Impairment of leasehold											23,700
Predecessor | Proved oil and natural gas properties
Net income (loss) per share/unit:
Impairment of oil and gas properties										$ 0	69,900		$ 69,900	$ 89,500
Royalty [Member]
Revenues			$ 5,000
Mid Continent and Premian Basin Property | Predecessor | Proved oil and natural gas properties
Net income (loss) per share/unit:
Impairment of oil and gas properties											49,500
Monroe Field Property | Predecessor | Proved oil and natural gas properties
Net income (loss) per share/unit:
Impairment of oil and gas properties											15,300
Central Texas Property | Proved oil and natural gas properties
Net income (loss) per share/unit:
Impairment of oil and gas properties												$ 3,100
Central Texas Property | Predecessor | Proved oil and natural gas properties
Net income (loss) per share/unit:
Impairment of oil and gas properties											2,200
East Texas Property | Predecessor | Proved oil and natural gas properties
Net income (loss) per share/unit:
Impairment of oil and gas properties											$ 2,900