Note 5 - Stock-based Compensation (Details Textual)	3 Months Ended
Mar. 31, 2024 $ / shares shares
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Grants in Period, Gross (in shares)	0
Restricted Stock [Member] \| Employee [Member] \| Minimum [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Award Vesting Period (Year)	3 years
Restricted Stock [Member] \| Employee [Member] \| Maximum [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Award Vesting Period (Year)	4 years
Restricted Stock [Member] \| Director [Member] \| Minimum [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Award Vesting Period (Year)	1 year
Restricted Stock [Member] \| Director [Member] \| Maximum [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Award Vesting Period (Year)	3 years
Restricted Stock Units (RSUs) [Member] \| Minimum [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Award Vesting Period (Year)	3 years
Restricted Stock Units (RSUs) [Member] \| Maximum [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Award Vesting Period (Year)	4 years
Performance Shares [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Award Vesting Period (Year)	3 years
Share-Based Payment Arrangement [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Number of Shares Available for Grant (in shares)	1,258
Share-Based Payment Arrangement, Option [Member]
Share Price (in dollars per share) \| $ / shares	$ 27.18

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.

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (a)(1)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480429/718-10-50-2

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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

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480429/718-10-50-2

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- Definition

Gross number of share options (or share units) granted during the period.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(iv)(01)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480429/718-10-50-2

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- Definition

Price of a single share of a number of saleable stocks of a company.

+ References

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