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Note 8 - Stock-based Compensation Expense (Details Textual) - USD ($) |  |  | 12 Months Ended |
--- | --- | --- | --- | ---
Aug. 03, 2020 | May 04, 2020 | Dec. 31, 2024 | Dec. 31, 2023 | Dec. 31, 2022 | Jun. 30, 2021
Share-Based Compensation Arrangement by Share-Based Payment Award, Number of Shares Available for Grant (in shares) |  |  | 578,000 |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period (in shares) |  |  | 120,000 |  |  |
Share-Based Payment Arrangement, Expense |  |  | $ 373,000 |  |  |
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Grants in Period, Gross (in shares) |  |  | 0 | 70,000 |  |
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value (in dollars per share) |  |  |  | $ 2.89 |  |
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Exercises in Period (in shares) |  |  | 0 | 0 |  |
Share-Based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount |  |  | $ 23,000 |  |  |
Share-Based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition (Year) |  |  | 3 years |  |  |
Stock Repurchase Program, Number of Shares Authorized to be Repurchased (in shares) |  |  | 1,000,000 |  |  |
Stock Repurchased During Period, Shares (in shares) |  |  | 0 | 0 |  |
Stock Repurchase Program, Remaining Number of Shares Authorized to be Repurchased (in shares) |  |  | 72,000 |  |  |
Restricted Stock Units (RSUs) [Member] |  |  |  |  |  |
Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Grants in Period (in shares) |  |  | 290,000 | 146,000 |  |
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period (in shares) |  |  | 120,000 | 116,000 |  |
Share-Based Compensation Arrangement by Share-Based Payment Award, Non-Option Equity Instruments, Outstanding, Number (in shares) |  |  | 206,000 | 36,000 | 6,000 |
Restricted Stock Units (RSUs) [Member] | Selling, General and Administrative Expenses [Member] |  |  |  |  |  |
Share-Based Payment Arrangement, Expense, after Tax |  |  | $ 373,000 | $ 389,000 |  |
Restricted Stock Units (RSUs) [Member] | Chief Executive Officer [Member] |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period (in shares) |  |  | 120,000 |  |  |
Share-Based Payment Arrangement, Expense |  |  | $ 352,000 |  |  |
Share-Based Payment Arrangement, Option [Member] |  |  |  |  |  |
Share-Based Payment Arrangement, Expense |  |  | $ 17,000 | 34,000 |  |
Incentive Compensation Plan [Member] |  |  |  |  |  |
Common Stock, Capital Shares Reserved for Future Issuance (in shares) |  |  |  |  |  | 2,580,000
Incentive Compensation Plan [Member] | Restricted Stock Units (RSUs) [Member] |  |  |  |  |  |
Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Grants in Period (in shares) |  |  | 1,188,000 |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period (in shares) |  |  | 123,000 |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Non-Option Equity Instruments, Vested And Expected To Vest, Outstanding, Number (in shares) |  |  | 864,000 |  |  |
Share-Based Compensation Arrangement by Share-Based Payment Award, Non-Option Equity Instruments, Outstanding, Number (in shares) |  |  | 206,000 |  |  |
Incentive Compensation Plan [Member] | Restricted Stock Units (RSUs) [Member] | Employees [Member] |  |  |  |  |  |
Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Grants in Period (in shares) |  |  | 58,000 |  |  |
Incentive Compensation Plan [Member] | Restricted Stock Units (RSUs) [Member] | Chief Executive Officer [Member] |  |  |  |  |  |
Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Grants in Period (in shares) |  |  | 750,000 |  |  |
Incentive Compensation Plan [Member] | Restricted Stock Units (RSUs) [Member] | Non Employee Directors and Corporate Secretary [Member] |  |  |  |  |  |
Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Grants in Period (in shares) |  |  | 53,000 |  |  |
Incentive Compensation Plan [Member] | Restricted Stock Units (RSUs) [Member] | Non Employee Directors [Member] |  |  |  |  |  |
Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Grants in Period (in shares) |  |  | 327,000 |  |  |
Executive Equity Awards [Member] | Restricted Stock Units (RSUs) [Member] |  |  |  |  |  |
Share-Based Payment Arrangement, Expense |  |  | $ 352,000 | $ 351,000 |  |
Executive Equity Awards [Member] | Restricted Stock Units (RSUs) [Member] | Chief Executive Officer [Member] |  |  |  |  |  |
Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Grants in Period (in shares) | 10,000 | 50,000 |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period (in shares) |  |  | 90,000 | 90,000 |  |
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period (Day) | 30 days |  |  |  |  |
Stock Issued During Period, Shares, Issued for Services (in shares) |  |  | 120,000 |  | 120,000 |

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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 + Details
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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 + Details
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