Note 6 - Exploratory Well Costs - Exploratory Well Costs (Details) - USD ($) $ in Thousands	4 Months Ended	6 Months Ended	8 Months Ended	12 Months Ended
Dec. 31, 2020	Jun. 30, 2021	Aug. 21, 2020	Dec. 31, 2019
Beginning capitalized exploratory well costs	$ 41,524	$ 32,592	$ 11,427	$ 0
Additions to exploratory well costs	53,462	75,289	48,169	58,435
Reclassification to proved properties	(62,394)	(106,749)	(18,072)	(47,008)
Exploratory well costs charged to exploration and abandonment expense	0	0	0	0
Ending capitalized exploratory well costs	$ 32,592	$ 1,132	$ 41,524	$ 11,427

Additions to capitalized exploratory well costs that were added during the reporting period pending the determination of proved reserves.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 932
-SubTopic 235
-Section 50
-Paragraph 1B
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=123377692&loc=SL6806780-109447

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- Definition

Amount of expense for capitalized exploratory well costs for which proved reserves were not found at the exploratory well.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 932
-SubTopic 235
-Section 50
-Paragraph 1B
-Subparagraph (a)(3)
-URI http://asc.fasb.org/extlink&oid=123377692&loc=SL6806780-109447

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- Definition

The amount of capitalized exploratory well costs that is pending the determination of proved reserves. This does not include amounts that were capitalized and subsequently expensed in the same annual period.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 932
-SubTopic 235
-Section 50
-Paragraph 1B
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=123377692&loc=SL6806780-109447

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- Definition

Previously capitalized costs of the drilling of wells that were reclassified as part of the costs of the enterprise's wells and related equipment and facilities at the time that proved reserves were found.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 932
-SubTopic 235
-Section 50
-Paragraph 1B
-Subparagraph (a)(2)
-URI http://asc.fasb.org/extlink&oid=123377692&loc=SL6806780-109447

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