ASSET RETIREMENT OBLIGATIONS (Details) - USD ($) $ in Thousands	1 Months Ended	11 Months Ended	12 Months Ended
Feb. 08, 2018	Dec. 31, 2018	Dec. 31, 2019
Asset Retirement Obligation, Roll Forward Analysis [Roll Forward]
Balance, beginning of period	$ 10,469	$ 10,509	$ 11,552
Liabilities assumed in Business Combination	0	5,998	0
Liabilities incurred	0	2,676	859
Liabilities settled	(63)	(1,610)	(234)
Liabilities transferred via sale	0	(19)	0
Revisions to estimates	63	3,766	26
Accretion expense	40	741	980
Balance, end of period	10,509	11,552	13,183
Less: Current portion	33	2,079	34
Long-term portion	$ 10,476	$ 9,473	$ 13,149
Asset retirement obligation, measurement input, interest rates		10.20%
Minimum
Asset Retirement Obligation, Roll Forward Analysis [Roll Forward]
Asset retirement obligation, measurement input, interest rates	4.40%
Maximum
Asset Retirement Obligation, Roll Forward Analysis [Roll Forward]
Asset retirement obligation, measurement input, interest rates	8.80%

Asset Retirement Obligation, Liabilities Assumed In Business Combination

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- Definition

Asset Retirement Obligation, Liabilities Transferred In Sale of Properties

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No definition available.

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- Definition

Asset Retirement Obligation, Measurement Input, Debt Interest Rate

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- Definition

The carrying amount of a liability for an asset retirement obligation. An asset retirement obligation is a legal obligation associated with the disposal or retirement of a tangible long-lived asset that results from the acquisition, construction or development, or the normal operations of a long-lived asset, except for certain obligations of lessees.

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- Definition

Amount of accretion expense recognized during the period that is associated with an asset retirement obligation. Accretion expense measures and incorporates changes due to the passage of time into the carrying amount of the liability.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 410
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (c)(3)
-URI http://asc.fasb.org/extlink&oid=6392692&loc=d3e7535-110849

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 410
-SubTopic 20
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6392676&loc=d3e7480-110848

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Current portion of the carrying amount of a liability for an asset retirement obligation. An asset retirement obligation is a legal obligation associated with the disposal or retirement of a tangible long-lived asset that results from the acquisition, construction or development, or the normal operations of a long-lived asset, except for certain obligations of lessees.

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Amount of asset retirement obligations incurred during the period.

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Amount of asset retirement obligations settled, or otherwise disposed of, during the period. This may include asset retirement obligations transferred to third parties associated with the sale of a long-lived asset.

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Amount of increase (decrease) in the asset retirement obligation from changes in the amount or timing of the estimated cash flows associated with the settlement of the obligation.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 410
-SubTopic 20
-Section 35
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=6392603&loc=d3e7123-110846

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-URI http://asc.fasb.org/extlink&oid=6392692&loc=d3e7535-110849

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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Noncurrent portion of the carrying amount of a liability for an asset retirement obligation. An asset retirement obligation is a legal obligation associated with the disposal or retirement of a tangible long-lived asset that results from the acquisition, construction or development, or the normal operations of a long-lived asset, except for certain obligations of lessees.

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