Note 5 - Derivative Instruments - Impact From Derivatives on Consolidated Statements of Comprehensive Income (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Derivatives	$ (13)	$ (81)
Interest Rate Swap [Member] | ABL Credit Facility [Member]
Derivatives		(61)
Interest Rate Swap [Member] | Chicago Tube and Iron Company Acquisition [Member]
Derivatives	(13)	(20)
Metals Swap [Member]
Derivatives	14	(76)
Embedded Customer Derivatives [Member]
Derivatives	$ (14)	$ 76