Note 4 - Earnings Per Share (Details Textual) - shares	3 Months Ended	6 Months Ended
Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Dilutive Securities Included in Computation of Earnings Per Share Amount Stock Option	135,163	906,404	135,163	659,488
Dilutive Securities Included in Computation of Earnings Per Share Amount Restricted Stock	5,000	14,164	5,000	14,164
Incremental Common Shares Attributable to Dilutive Effect of Share-Based Payment Arrangements	20,352	240,259	24,751	197,848
Share-Based Payment Arrangement, Option [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount	1,073,077	414,916	1,073,077	414,916

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

No definition available.

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- Definition

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

+ References

No definition available.

+ Details

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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
-Topic 260
-SubTopic 10
-Section 45
-Paragraph 22
-URI https://asc.fasb.org/extlink&oid=126958026&loc=d3e1707-109256

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 260
-SubTopic 10
-Section 50
-Paragraph 1
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-URI https://asc.fasb.org/extlink&oid=124432515&loc=d3e3550-109257

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-Publisher FASB
-Name Accounting Standards Codification
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-Section 45
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-URI https://asc.fasb.org/extlink&oid=126958026&loc=d3e1500-109256

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 260
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-Section 45
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-URI https://asc.fasb.org/extlink&oid=126958026&loc=d3e1757-109256

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