Note 6 - Goodwill and Intangible Assets - Goodwill, by Reportable Segment (Details) $ in Thousands	9 Months Ended
Sep. 30, 2018 USD ($)
Balance as of December 31, 2017
Acquisitions	2,358
Impairments
Balance as of September 30, 2018	2,358
Carbon Flat Products [Member]
Balance as of December 31, 2017
Acquisitions
Impairments
Balance as of September 30, 2018
Specialty Metals Flat Products [Member]
Balance as of December 31, 2017
Acquisitions	2,358
Impairments
Balance as of September 30, 2018	2,358
Tubular and Pipe Products [Member]
Balance as of December 31, 2017
Acquisitions
Impairments
Balance as of September 30, 2018

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
-Paragraph 5
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Amount of increase in asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized resulting from a business combination.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 50
-Paragraph 1
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Amount of loss from the write-down of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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-Name Accounting Standards Codification
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-Publisher FASB
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