Note 10 - Share-based Compensation (Details Textual) - USD ($)	3 Months Ended
Mar. 31, 2024	Mar. 31, 2023
Share-Based Payment Arrangement, Expense	$ 163,000	$ 196,000
Share-Based Payment Arrangement, Expense, Tax Benefit	39,000	$ 47,000
Share-Based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount	$ 2,100,000
Share-Based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition (Year)	2 years 2 months 26 days
Restricted Stock Units (RSUs) [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Grants in Period (in shares)	0	0
The 2014 Long-term Incentive Plan [Member] \| A 7 Year Vesting Stock Appreciation Rights [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Grants in Period (in shares)		67,637
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value (in dollars per share)		$ 8.77
Share-Based Compensation Arrangement by Share-Based Payment Award, Award Vesting Period (Year)		7 years
Share-Based Compensation Arrangement by Share-Based Payment Award, Expiration Period (Year)		10 years
The 2014 Long-term Incentive Plan [Member] \| A 7 Year Vesting Stock Appreciation Rights [Member] \| Vesting Per Year [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Award Vesting Rights, Percentage		14.30%
The 2014 Long-term Incentive Plan [Member] \| A 5 Year Vesting Stock Appreciation Rights [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Grants in Period (in shares)		108,747
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value (in dollars per share)		$ 8.63
Share-Based Compensation Arrangement by Share-Based Payment Award, Award Vesting Period (Year)		5 years
Share-Based Compensation Arrangement by Share-Based Payment Award, Expiration Period (Year)		10 years
The 2014 Long-term Incentive Plan [Member] \| A 5 Year Vesting Stock Appreciation Rights [Member] \| Vesting Per Year [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Award Vesting Rights, Percentage		20.00%
The 2014 Long-term Incentive Plan [Member] \| Stock Appreciation Rights (SARs) [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Grants in Period (in shares)	0
The 2014 Long-term Incentive Plan [Member] \| Restricted Stock Units (RSUs) [Member] \| Minimum [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Award Vesting Period (Year)	3 years
The 2014 Long-term Incentive Plan [Member] \| Restricted Stock Units (RSUs) [Member] \| Maximum [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Award Vesting Period (Year)	5 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 S99
-Paragraph 1
-Subparagraph (SAB Topic 14.F)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479830/718-10-S99-1

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
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-Section 50
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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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Amount of tax benefit for recognition of expense of award under share-based payment arrangement.

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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.

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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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The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

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

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Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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