Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

No definition available.

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- Definition

Gain (loss) incurred in hedging activities.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4A
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=84234895&loc=SL5618551-113959

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- Definition

The difference between the book value and the sale price of options, swaps, futures, forward contracts, and other derivative instruments. This element refers to the gain (loss) included in earnings.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 225
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-04.13(h))
-URI http://asc.fasb.org/extlink&oid=6879574&loc=d3e536633-122882

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3602-108585

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- Definition

The net change in the difference between the fair value and the carrying value, or in the comparative fair values, of derivative instruments, including options, swaps, futures, and forward contracts, held at each balance sheet date, that was included in earnings for the period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3602-108585

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- Details

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DERIVATIVE AND HEDGING ACTIVITIES - Realized Unrealized (Details) - USD ($) $ in Thousands	4 Months Ended	8 Months Ended	12 Months Ended
	Dec. 31, 2016	Sep. 09, 2016	Dec. 31, 2018	Dec. 31, 2017
Derivative and hedging activities
Total net gain (loss) on derivative contracts	$ (27,740)		$ 92,625	$ 1,291
Derivatives not designated as hedging contracts \| Commodity contracts \| Other Income Expense
Derivative and hedging activities
Unrealized gain (loss) on commodity contracts	(112,449)		84,274	(16,468)
Realized gain (loss) on commodity contracts	84,709		8,351	17,759
Total net gain (loss) on derivative contracts	$ (27,740)		$ 92,625	$ 1,291
Predecessor
Derivative and hedging activities
Total net gain (loss) on derivative contracts		$ (17,998)
Predecessor \| Derivatives not designated as hedging contracts \| Commodity contracts \| Other Income Expense
Derivative and hedging activities
Unrealized gain (loss) on commodity contracts		(263,732)
Realized gain (loss) on commodity contracts		245,734
Total net gain (loss) on derivative contracts		$ (17,998)