FAIR VALUE MEASUREMENTS (Fair Value Hierarchy for Assets and Liabilities Measured at Fair Value on Recurring Basis) (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
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Financial Designation, Predecessor and Successor [Fixed List]	Predecessor	Successor	Successor	Successor	Predecessor	Predecessor
Derivative asset, fair value		$ 26,613	$ 6,231	$ 26,613
Equity securities		47,082		47,082
Derivative liability, fair value		3,827		3,827
Recurring basis
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Equity securities		47,082		47,082
Total, Derivative asset, fair value		73,695		73,695
Recurring basis | Commodity contracts
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Derivative asset, fair value		26,613	6,231	26,613
Derivative liability, fair value		3,827		3,827
Recurring basis | Quoted Prices in Active Markets for Identical Assets (Level 1)
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Equity securities		47,082		47,082
Total, Derivative asset, fair value		47,082		47,082
Recurring basis | Significant Other Observable Inputs (Level 2)
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total, Derivative asset, fair value		26,613		26,613
Recurring basis | Significant Other Observable Inputs (Level 2) | Commodity contracts
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Derivative asset, fair value		26,613	$ 6,231	26,613
Derivative liability, fair value		$ 3,827		$ 3,827