Note 7 - Income Taxes (Details Textual) - USD ($)	6 Months Ended
Jun. 30, 2023	Dec. 31, 2022
Unrecognized Tax Benefits that Would Impact Effective Tax Rate	$ 5,300,000	$ 5,300,000
Unrecognized Tax Benefits, Interest on Income Taxes Accrued	$ 302,000	$ 302,000
Domestic Tax Authority [Member]
Open Tax Year	2019 2020 2021 2022
State and Local Jurisdiction [Member]
Open Tax Year	2018 2019 2020 2021 2022

Tax year that remains open to examination under enacted tax laws, in YYYY format.

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

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- Definition

Amount of interest expense accrued for an underpayment of income taxes.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 740
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 15
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482685/740-10-50-15

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- Definition

The total amount of unrecognized tax benefits that, if recognized, would affect the effective tax rate.

+ References

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

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