Note 17 - Supplemental Oil and Gas Disclosures (Unaudited) - Cost Incurred in Oil and Natural Gas Property Acquisition, Exploration and Development (Details) - USD ($) $ in Thousands	4 Months Ended	8 Months Ended	12 Months Ended
Dec. 31, 2020	Aug. 21, 2020	Dec. 31, 2019
Proved properties	$ 0	$ 585	$ 4,635
Unproved properties	1,181	2,753	6,288
Total acquisition costs	1,181	3,338	10,923
Exploration costs	52,837	48,801	59,349
Development costs	11,757	863	54
Oil and gas expenditures	65,775	53,002	70,326
Asset retirement obligations, net	105	(98)	(316)
Total costs incurred	$ 65,670	$ 53,100	$ 70,642

Amount of asset retirement obligation incurred related to oil and gas property acquisition.

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- Definition

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

+ References

No definition available.

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- Definition

Cost incurred, including capitalized costs and costs charged to expense, in acquisition of oil and gas properties.

+ References

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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=123377692&loc=d3e62038-109447

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-Publisher FASB
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-SubTopic 235
-Section 50
-Paragraph 18
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=123377692&loc=d3e62014-109447

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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=123377692&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=123377692&loc=d3e62038-109447

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

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

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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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