Note 6 - Renewable Energy Tax Credit Investment (Details Textual) - USD ($)	3 Months Ended	6 Months Ended
Jun. 30, 2024	Mar. 31, 2024	Jun. 30, 2023	Jun. 30, 2024	Dec. 31, 2023
Amortization of Solar Energy Tax Credit Investment	$ 337,000			$ 842,000
Income Tax Credits and Adjustments		$ 425,000	$ 0	1,000,000
Financial Standby Letter of Credit [Member]
Guarantor Obligations, Maximum Exposure, Undiscounted	2,000,000			2,000,000
Investment Tax Credit Carryforward [Member]
Tax Credit, Committed Investment in the Tax Credit Producing Entity	$ 1,500,000			$ 1,500,000	$ 306,000

The aggregate amount of recurring noncash expense charged against earnings in the period to allocate the cost of solar energy tax credit investment.

No definition available.

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- Definition

Represents the Committed Investment in the Tax Credit Producing Entity

+ References

No definition available.

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- Definition

Maximum potential amount of future payments (undiscounted) the guarantor could be required to make under the guarantee or each group of similar guarantees before reduction for potential recoveries under recourse or collateralization provisions.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 460
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 4
-Subparagraph (b)(1)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482425/460-10-50-4

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A credit or adjustment for government or taxing authority authorized decrease in taxes owed as a result of meeting certain tax policy conditions.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 230
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 28
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482740/230-10-45-28

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