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Note 2 - Summary of Significant Accounting Policies (Details Textual)		1 Months Ended		12 Months Ended
	Mar. 30, 2014 USD ($)	Apr. 30, 2015 USD ($)	Sep. 30, 2014 USD ($)	Dec. 31, 2016 USD ($)	Dec. 31, 2015 USD ($)	Dec. 31, 2014 USD ($)
Investments				$ 0	$ 0
Discontinued Operation, Gain (Loss) from Disposal of Discontinued Operation, before Income Tax						$ (13,497,000)
Proceeds from Divestiture of Businesses					4,300,000	29,791,000
Book Overdrafts				0	$ 0
Workers' Compensation Liability				$ 3,400,000
Number of Customers with Receivable Balance in Excess of Ten Percent of Receivables				2	0
Accrued Liability [Member]
Workers' Compensation Liability, Current				$ 600,000
Other Long-term Liabilities [Member]
Workers' Compensation Liability, Noncurrent				$ 2,800,000
Minimum [Member]
Finite-Lived Intangible Asset, Useful Life				3 years
Maximum [Member]
Finite-Lived Intangible Asset, Useful Life				15 years
Land Improvements [Member] | Minimum [Member]
Property, Plant and Equipment, Useful Life				15 years
Land Improvements [Member] | Maximum [Member]
Property, Plant and Equipment, Useful Life				30 years
Building [Member] | Minimum [Member]
Property, Plant and Equipment, Useful Life				20 years
Building [Member] | Maximum [Member]
Property, Plant and Equipment, Useful Life				40 years
Machinery and Equipment [Member] | Minimum [Member]
Property, Plant and Equipment, Useful Life				3 years
Machinery and Equipment [Member] | Maximum [Member]
Property, Plant and Equipment, Useful Life				30 years
Disposal of OCTG Business [Member]
Proceeds from Sale of Productive Assets	$ 42,700,000
Discontinued Operation, Gain (Loss) from Disposal of Discontinued Operation, before Income Tax	13,500,000		$ 1,800,000
Goodwill, Written off Related to Sale of Business Unit						4,400,000
Business Acquisition Purchase Price Amount Held In Escrow To Secure Indemnification Obligations	4,300,000
Repayments of Debt and Capital Lease Obligations	5,000,000
Business Acquisition, Transaction Costs	$ 1,800,000
Proceeds from Divestiture of Businesses						$ 29,800,000
Escrow Deposit Released		$ 4,300,000

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