Note 10 - Supplemental Financial Data - Oil and Gas Producing Activities (Unaudited): Capitalized Costs Relating to Oil and Gas Producing Activities Disclosure (Details) - USD ($)	Sep. 30, 2023	Sep. 30, 2022
Details
Proved, developed properties	$ 326,000	$ 327,000
Less: accumulated depreciation, depletion and impairment	(297,000)	(292,000)
Capitalized Costs, Oil and Gas Producing Activities, Net	$ 29,000	$ 35,000

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

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 932
-SubTopic 235
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482274/932-235-50-13

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- Definition

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

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- Definition

Capitalized costs of proved properties incurred for any combination mineral interests acquisitions; wells and related equipment; support equipment and facilities; and uncompleted wells and equipment and other costs not previously disclosed within this table.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 932
-SubTopic 360
-Name Accounting Standards Codification
-Publisher FASB
-URI https://asc.fasb.org//932-360/tableOfContent

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 932
-SubTopic 235
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
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-URI https://asc.fasb.org//1943274/2147482274/932-235-50-13

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