Note 4 - Earnings Per Share (Details Textual) - shares	3 Months Ended	9 Months Ended
Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
Dilutive Securities Included in Computation of Earnings Per Share Amount Stock Option			128,665	598,489
Dilutive Securities Included in Computation of Earnings Per Share Amount Restricted Stock			5,000	14,164
Incremental Common Shares Attributable to Dilutive Effect of Share-Based Payment Arrangements			22,203	179,951
Share-Based Payment Arrangement, Option [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount	1,202,076	1,064,656	1,073,411	466,167
Restricted Stock [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount	5,000	14,164

Number of employee stock options included in calculation of diluted earnings per share.

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- Definition

Number of restricted shares included in calculation of diluted earnings per share.

+ References

No definition available.

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- Definition

Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted EPS or EPU because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 260
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (c)
-URI https://asc.fasb.org/extlink&oid=124432515&loc=d3e3550-109257

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- Definition

Additional shares included in the calculation of diluted EPS as a result of the potentially dilutive effect of share based payment arrangements using the treasury stock method.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 45
-Paragraph 1
-URI https://asc.fasb.org/extlink&oid=126962052&loc=d3e4991-113900

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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-URI https://asc.fasb.org/extlink&oid=126958026&loc=d3e1707-109256

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
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-Name Accounting Standards Codification
-Topic 260
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-URI https://asc.fasb.org/extlink&oid=124432515&loc=d3e3550-109257

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-Publisher FASB
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-URI https://asc.fasb.org/extlink&oid=126958026&loc=d3e1500-109256

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-Publisher FASB
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