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RISK MANAGEMENT (Fair Value of Derivatives) (Details) - USD ($) $ in Thousands	5 Months Ended	7 Months Ended	12 Months Ended
	May 31, 2018	Dec. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Derivatives, Fair Value [Line Items]
Financial Designation, Predecessor and Successor [Fixed List]	Predecessor	Successor	Successor	Successor	Predecessor	Predecessor
Derivative Assets [Abstract]
Derivative asset, fair value		$ 26,613	$ 6,231	$ 26,613
Derivative asset		15,452	6,231	15,452
Long–term derivative asset		8,499		8,499
Derivative asset, Net recorded fair value		23,951	6,231	23,951
Derivative Liabilities [Abstract]
Derivative liability, fair value		3,827		3,827
Derivative liability, asset		(2,662)		(2,662)
Derivative liability		1,165		1,165
Derivative liability, Net recorded fair value		1,165		1,165
Current Assets [Member]
Derivative Assets [Abstract]
Derivative asset, fair value		18,048	$ 6,231	18,048
Derivative Liabilities [Abstract]
Derivative liability, asset		(2,596)		(2,596)
Noncurrent Derivative Asset
Derivative Assets [Abstract]
Derivative asset, fair value		8,565		8,565
Derivative Liabilities [Abstract]
Derivative liability, asset		(66)		(66)
Current Derivatives Liability
Derivative Liabilities [Abstract]
Derivative liability, fair value		3,761		3,761
Derivative liability, asset		(2,596)		(2,596)
Noncurrent Derivative Liability
Derivative Liabilities [Abstract]
Derivative liability, fair value		66		66
Derivative liability, asset		$ (66)		$ (66)