SUPPLEMENTAL OIL AND GAS INFORMATION (UNAUDITED) - Costs Incurred (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Extractive Industries [Abstract]
Property acquisition costs, proved	$ 0	$ 0	$ 0
Property acquisition costs, unproved	5,821	6,072	29,851
Exploration costs	15,419	20,270	94,309
Development costs	546,646	761,326	778,574
Total costs	$ 567,886	$ 787,668	$ 902,734

No definition available.

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- Definition

Costs incurred, including capitalized costs and costs charged to expense, associated with the acquisition of oil and gas properties that have proved reserves.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 932
-SubTopic 235
-Section 50
-Paragraph 19
-URI http://asc.fasb.org/extlink&oid=68064819&loc=d3e62038-109447

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-URI http://asc.fasb.org/extlink&oid=68064819&loc=d3e62014-109447

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- Definition

Costs incurred, including capitalized costs and costs charged to expense, associated with the acquisition of oil and gas properties that have unproved reserves.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 932
-SubTopic 235
-Section 50
-Paragraph 18
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=68064819&loc=d3e62014-109447

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-Publisher FASB
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-Topic 932
-SubTopic 235
-Section 50
-Paragraph 19
-URI http://asc.fasb.org/extlink&oid=68064819&loc=d3e62038-109447

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- Definition

Development costs incurred, including capitalized costs and costs charged to expense, in oil and gas activities.

+ References

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- Definition

Exploration costs incurred, including capitalized costs and costs charged to expense, in oil and gas activities.

+ References

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Amount of costs incurred related to oil and gas property acquisition, exploration and development activities, including capitalized costs and costs charged to expense.

+ References

No definition available.

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