REVENUE (Schedule of Revenue Disaggregated by Product and Service) (Details) - USD ($) $ in Thousands	1 Months Ended	2 Months Ended	3 Months Ended							5 Months Ended	7 Months Ended	12 Months Ended
	Jun. 30, 2018	May 31, 2018	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Mar. 31, 2018	May 31, 2018	Dec. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Financial Designation, Predecessor and Successor [Fixed List]										Predecessor	Successor	Successor	Successor	Predecessor	Predecessor
Disaggregated revenues	$ 21,720	$ 43,089	$ 16,138	$ 23,249	$ 30,587	$ 43,846	$ 47,914	$ 68,966	$ 67,942	$ 111,031	$ 138,600	$ 113,820		$ 225,693
Revenue excluding royalty							52,900				143,600
Oil, natural gas and natural gas liquids revenues
Disaggregated revenues										110,307	137,169	112,419		223,297
Revenue excluding royalty											142,200
Oil Product [Member]
Disaggregated revenues										42,460	41,411	32,004
Natural Gas Product [Member]
Disaggregated revenues										40,951	63,460	60,035
Natural Gas Liquids Product [Member]
Disaggregated revenues										26,896	32,298	20,380
Revenue excluding royalty											37,300
Wet Gas Products [Member]
Disaggregated revenues										8,400	13,400	4,400
Wet Gas Natural Gas [Member]
Disaggregated revenues										3,200	4,400	1,500
Wet Gas Natural Gas Liquids [Member]
Disaggregated revenues										5,200	9,000	2,900
Transportation and marketing–related revenues
Disaggregated revenues										$ 724	1,431	$ 1,401		$ 2,396
Royalty [Member]
Disaggregated revenues							$ 5,000				$ 5,000