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Note 1 - Summary of Significant Accounting Policies (Details Textual) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2021 USD ($) | Dec. 31, 2020 USD ($) | Dec. 31, 2019 USD ($)
Percentage of LIFO Inventory | 72.00% | 71.00% |
Depreciation, Total | $ 11,200 | $ 11,400 | $ 12,600
Goodwill, Impairment Loss | 0 | 0 | 0
Advertising Expense | 1,900 | 2,100 | 3,000
Performance Shares [Member] |  |  |
Share-based Payment Arrangement, Expense | $ 2,000 | $ 300 | $ 700
The 2015 Omnibus Incentive Plan [Member] | Minimum [Member] |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period (Year) | 2 years |  |
The 2015 Omnibus Incentive Plan [Member] | Maximum [Member] |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period (Year) | 3 years |  |
Customer Concentration Risk [Member] | Revenue Benchmark [Member] |  |  |
Number of Major Customers | 0 | 0 | 0

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