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Note 8 - Stock-based Compensation Expense (Details Textual) - USD ($) |  |  | 12 Months Ended |  |
--- | --- | --- | --- | --- | ---
Aug. 03, 2020 | May 04, 2020 | Dec. 31, 2022 | Dec. 31, 2021 | Jun. 30, 2021 | Dec. 31, 2020
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period (in shares) |  |  | 135,000 |  |  |
Share-Based Payment Arrangement, Expense |  |  | $ 399,000 |  |  |
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value (in dollars per share) |  |  | $ 1.49 | $ 1.10 |  |
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Exercises in Period (in shares) |  |  | 4,000 | 22,000 |  |
Options Issued During Period, Cashless Stock Options Exercised (in shares) |  |  | 3,000 | 5,000 |  |
Proceeds from Stock Options Exercised |  |  | $ 5,000 | $ 5,000 |  |
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period Using Cash (in shares) |  |  | 2,000 | 2,000 |  |
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) |  |  | 131,000 | 165,000 |  |
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period (in shares) |  |  | 132,000 | 168,000 |  |
Share-Based Compensation Arrangement by Share-Based Payment Award, Non-Option Equity Instruments, Outstanding, Number, Ending Balance (in shares) |  |  | 6,000 | 10,000 |  | 13,000
Restricted Stock Units (RSUs) [Member] | Selling, General and Administrative Expenses [Member] |  |  |  |  |  |
Share-Based Payment Arrangement, Expense |  |  |  | $ 420,000 |  |
Share-Based Payment Arrangement, Expense, after Tax |  |  | $ 399,000 |  |  |
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 |  |  | $ 288,000 |  |  |
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, Vested in Period (in shares) |  |  | 1,000 |  |  |
Share-Based Payment Arrangement, Expense |  |  | $ 6,000 |  |  |
Share-Based Payment Arrangement, Option [Member] |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period (in shares) |  |  | 3,000 |  |  |
Share-Based Payment Arrangement, Expense |  |  | $ 10,000 | 2,000 |  |
Share-Based Payment Arrangement, Nonvested Award, Option, Cost Not yet Recognized, Amount |  |  | $ 80,000 |  |  |
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition (Year) |  |  | 4 years |  |  |
Incentive Compensation Plan [Member] |  |  |  |  |  |
Common Stock, Capital Shares Reserved for Future Issuance (in shares) |  |  |  |  | 2,580,000 |
Share-Based Compensation Arrangement by Share-Based Payment Award, Number of Shares Available for Grant (in shares) |  |  | 1,219,000 |  |  |
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) |  |  | 752,000 |  |  |
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) |  |  | 624,000 |  |  |
Share-Based Compensation Arrangement by Share-Based Payment Award, Non-Option Equity Instruments, Outstanding, Number, Ending Balance (in shares) |  |  | 6,000 |  |  |
Share-Based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount, Total |  |  | $ 11,000 |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Non-Option Equity Instruments, Vested, Deferred for Issuance (in shares) |  |  | 38,000 |  |  |
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) |  |  | 31,000 |  |  |
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) |  |  | 340,000 |  |  |
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 |  |  |
Share-Based Payment Arrangement, Expense |  |  | $ 6,000 |  |  |
Share-Based Payment Arrangement, Expense, Tax Benefit |  |  | $ 1,500 |  |  |
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) |  |  | 328,000 |  |  |
Executive Equity Awards [Member] | Restricted Stock Units (RSUs) [Member] |  |  |  |  |  |
Share-Based Payment Arrangement, Expense |  |  | $ 288,000 | $ 331,000 |  |
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, Award Vesting Period (Day) | 30 days |  |  |  |  |
Stock Issued During Period, Shares, Issued for Services (in shares) |  |  | 120,000 | 120,000 |  |

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