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v3.21.2

Note 1 - Basis of Presentation and Accounting Policies (Details Textual) - USD ($) $ in Thousands | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2021 | Sep. 30, 2020 | Sep. 30, 2021 | Sep. 30, 2020
Cost of Goods and Services Sold, Total | $ 110,992 | $ 91,183 | $ 301,234 | $ 259,286
Nonoperating Income (Expense), Total | (201) | (483) | 458 | (1,390)
Supplemental Employee Retirement Plan [Member] |  |  |  |
Defined Benefit Plan, Net Periodic Benefit Cost (Credit), Total | $ 431 | 395 | $ 1,295 | 1,185
Revision of Prior Period, Adjustment [Member] | Cost of Sales Reclassified to Other (Expense) Income, Net [Member] |  |  |  |
Defined Benefit Plan, Net Periodic Benefit Cost (Credit), Total |  |  |  | 200
Cost of Goods and Services Sold, Total |  | 200 |  |
Nonoperating Income (Expense), Total |  |  |  | 100
Revision of Prior Period, Adjustment [Member] | Selling, General and Administrative Expenses Reclassified to Other (Expense) Income, Net [Member] |  |  |  |
Cost of Goods and Services Sold, Total |  | 500 |  |
Nonoperating Income (Expense), Total |  |  |  | $ 100
Revision of Prior Period, Adjustment [Member] | Supplemental Employee Retirement Plan [Member] |  |  |  |
Defined Benefit Plan, Net Periodic Benefit Cost (Credit), Total |  | $ (700) |  |

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