Note 8 - Stock-based Compensation (Details Textual) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2024	Mar. 31, 2023
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Grants in Period, Gross (in shares)	0
Deferred Compensation Plan for Directors [Member]
Deferred Compensation Arrangement with Individual, Compensation Expense	$ 0	$ 0
The 2014 Long-term Incentive Plan [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Number of Shares Authorized (in shares)	5,742,376
Share-Based Compensation Arrangement by Share-Based Payment Award, Number of Shares Available for Grant (in shares)	1,106,450
Share-Based Payment Arrangement, Expense, Tax Benefit	$ 0	$ 0
The 2014 Long-term Incentive Plan [Member] \| Share-Based Payment Arrangement, Option [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Expiration Period (Year)	10 years
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Grants in Period, Gross (in shares)	0
The 2014 Long-term Incentive Plan [Member] \| Share-Based Payment Arrangement, Option [Member] \| Share-Based Payment Arrangement, Tranche One [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage	50.00%
The 2014 Long-term Incentive Plan [Member] \| Share-Based Payment Arrangement, Option [Member] \| Share-Based Payment Arrangement, Tranche Two [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage	25.00%
The 2014 Long-term Incentive Plan [Member] \| Share-Based Payment Arrangement, Option [Member] \| Share-Based Payment Arrangement, Tranche Three [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage	25.00%
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)	2 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)	4 years
The 2014 Long-term Incentive Plan [Member] \| Restricted Stock Units (RSUs) [Member] \| Tranche One, If Look-Back RSUs Awarded [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage	33.33%
The 2014 Long-term Incentive Plan [Member] \| Restricted Stock Units (RSUs) [Member] \| Tranche Two, If Look-Back RSUs Awarded [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage	33.33%
The 2014 Long-term Incentive Plan [Member] \| Restricted Stock Units (RSUs) [Member] \| Tranche Three, If Look-Back RSUs Awarded [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage	33.33%
The 2014 Long-term Incentive Plan [Member] \| Restricted Stock Units (RSUs) [Member] \| Vesting If Total Revenue RSU, New Business Growth RSU, or Operating Income Growth RSU Awarded [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage	100.00%
The 2014 Long-term Incentive Plan [Member] \| Restricted Stock [Member]
Share-Based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount	$ 1,135
Share-Based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition (Year)	1 year 9 months 21 days
Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Vested in Period, Fair Value	$ 0

The compensation expense recognized during the period pertaining to the deferred compensation 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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Number of shares authorized for issuance under share-based payment arrangement.

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

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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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