Note 2 - Income Tax Expense - Reconciliation of Beginning and Ending Amount of Unrecognized Tax Benefits (Details)	9 Months Ended
Sep. 30, 2023 USD ($)
Unrecognized tax benefits as of December 31, 2022	$ 612,000
Additions/adjustments for tax positions of current year	0
Additions/adjustments for tax positions of prior years	(43,000)
Reductions for settlements with taxing authorities	0
Reductions for lapses of the applicable statutes of limitations	0
Unrecognized tax benefits as of March 31, 2023	$ 569,000

Amount of unrecognized tax benefits.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 15A
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482685/740-10-50-15A

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-SubTopic 10
-Name Accounting Standards Codification
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Amount of decrease in unrecognized tax benefits resulting from tax positions taken in prior period tax returns.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 15A
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Amount of decrease in unrecognized tax benefits resulting from settlements with taxing authorities.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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Amount of increase in unrecognized tax benefits resulting from tax positions that have been or will be taken in current period tax return.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-SubTopic 10
-Name Accounting Standards Codification
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Amount of decrease in unrecognized tax benefits resulting from lapses of applicable statutes of limitations.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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-SubTopic 10
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-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482685/740-10-50-15A

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