SUPPLEMENTAL OIL AND GAS INFORMATION (UNAUDITED) - Capitalized Costs (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Extractive Industries [Abstract]
Aggregate capitalized costs relating to oil and gas producing activities	$ 7,154,452	$ 6,676,122	$ 5,995,194
Aggregate accumulated depreciation, depletion and amortization	(3,148,564)	(2,861,014)	(2,540,068)
Net capitalized costs	$ 4,005,888	$ 3,815,108	$ 3,455,126

No definition available.

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- Definition

Amount of accumulated depreciation, depletion, amortization and valuation allowance relating to oil and gas producing activities.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 932
-SubTopic 235
-Section 50
-Paragraph 13
-URI http://asc.fasb.org/extlink&oid=68064819&loc=d3e61901-109447

+ Details

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- Definition

The sum of capitalized costs relating to oil and gas producing activities before accounting for accumulated depreciation.

+ References

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- Definition

Net amount of capitalized costs relating to oil and gas producing activities.

+ References

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