Note 8 - Stock-based Compensation (Details Textual) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2023 USD ($) shares	Jun. 30, 2023 USD ($) shares
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Grants in Period, Gross (in shares) \| shares		0
Deferred Compensation Plan for Directors [Member]
Deferred Compensation Arrangement with Individual, Compensation Expense \| $		$ 0
The 2014 Long-term Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized (in shares) \| shares	5,600,676	5,600,676
Share-Based Compensation Arrangement by Share-Based Payment Award, Number of Shares Available for Grant (in shares) \| shares	1,779,250	1,779,250
Share-Based Payment Arrangement, Expense, Tax Benefit \| $	$ 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) \| 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]
Share-Based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount \| $	$ 1,772	$ 1,772
Share-Based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition (Year)		2 years 1 month 24 days
Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Vested in Period, Fair Value \| $		$ 62
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 compensation expense recognized during the period pertaining to the deferred compensation arrangement.

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