Note 9 - Share-based Compensation - Shares Authorized, Available for Future Grant and Outstanding Under Each Plan (Details)	Dec. 31, 2024 shares
Authorized (in shares)	2,100,000
Available (in shares)	1,235,958
Outstanding (in shares)	607,085
The 2016 Plan [Member]
Authorized (in shares)	1,300,000
Available (in shares)	631,832
Outstanding (in shares)	399,211
The 2024 Directors Plan [Member]
Authorized (in shares)	800,000
Available (in shares)	604,126
Outstanding (in shares)	195,874
2014 Directors Plan [Member]
Authorized (in shares)	0
Available (in shares)	0
Outstanding (in shares)	12,000

Number of options and equity instrument other than options outstanding.

No definition available.

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- Definition

Number of shares authorized for issuance under share-based payment arrangement.

+ References

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-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
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-Publisher FASB
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- Definition

The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

+ References

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-SubTopic 10
-Section 50
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