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Note 1 - Summary of Significant Accounting Policies - Summary of Changes to Goodwill by Business Segment (Details) - USD ($) $ in Thousands | 12 Months Ended |
--- | --- | ---
Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017
Gross Balance |  | $ 37,572 | $ 37,572
Accumulated Impairments |  | 0 | 0
Balance | $ 37,572 | 37,572 | 37,572
Adjustments to Goodwill | 0 | 0 |
Manufacturing [Member] |  |  |
Gross Balance |  | 18,270 | 18,270
Accumulated Impairments |  | 0 | 0
Balance | 18,270 | 18,270 | 18,270
Adjustments to Goodwill | 0 | 0 |
Plastics [Member] |  |  |
Gross Balance |  | 19,302 | 19,302
Accumulated Impairments |  | 0 | 0
Balance | 19,302 | 19,302 | $ 19,302
Adjustments to Goodwill | $ 0 | $ 0 |

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