Note 2 - Stock-based Compensation (Details Textual) - USD ($)	6 Months Ended
Jun. 30, 2026	Jun. 30, 2025
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Outstanding, Number (in shares)	0
Share-Based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount	$ 1,260,000
Share-Based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition (Year)	3 years 9 months 18 days
Non-Employee Board Member Stock Option and Restricted Stock [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Grants in Period (in shares)	15,282
Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value (in dollars per share)	$ 15.7	$ 15.7
Non-Employee Board Member Stock Option and Restricted Stock [Member] \| Director [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage	100.00%
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period (Year)	1 year
Employee Deferred Stock Award [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period (Year)	4 years	4 years
Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Grants in Period (in shares)	36,200	27,400
Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value (in dollars per share)	$ 15.5	$ 19.43
Share-Based Payment Arrangement, Expense	$ 356,000	$ 331,000
Employee Deferred Stock Award [Member] \| Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period (Year)	1 year
Employee Deferred Stock Award [Member] \| Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period (Year)	4 years

Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section S45
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479983/718-10-S45-1

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SAB Topic 14.F)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479830/718-10-S99-1

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
-SubTopic 10
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-Section 50
-Paragraph 2
-Subparagraph (h)(1)(i)
-Publisher FASB
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Amount of cost not yet recognized for nonvested award under share-based payment arrangement.

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Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition.

+ References

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The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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Number of options outstanding, including both vested and non-vested options.

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Percentage of vesting of award under share-based payment arrangement.

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