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Note 4 - Goodwill and Intangible Assets - Schedule of Goodwill (Details) $ in Thousands | 9 Months Ended
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Sep. 30, 2020 USD ($)
Goodwill | $ 0
Goodwill | 22,985
Geneva Pipe Company, Inc [Member] |
Acquisition of Geneva (Note 2) | $ 22,985

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