Note 16 - Segment Information - Segment Reporting Information by Revenue (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018
Net sales	$ 445,919	$ 375,598
Depreciation and amortization	4,750	4,246
Operating income	6,074	12,345
Other income (loss), net	14	(46)
Income before interest and income taxes	6,088	12,299
Interest and other expense on debt	3,242	1,986
Income before income taxes	2,846	10,313
Carbon Flat Products [Member]
Net sales	278,536	240,894
Depreciation and amortization	2,814	2,560
Operating income	1,226	8,106
Specialty Metals Flat Products [Member]
Net sales	88,097	65,529
Depreciation and amortization	526	204
Operating income	2,244	3,011
Tubular and Pipe Products [Member]
Net sales	79,286	69,175
Depreciation and amortization	1,368	1,456
Operating income	5,615	4,267
Corporate Segment [Member]
Depreciation and amortization	42	26
Operating income	$ (3,011)	$ (3,039)

The current period expense charged against earnings on long-lived, physical assets not used in production, and which are not intended for resale, to allocate or recognize the cost of such assets over their useful lives; or to record the reduction in book value of an intangible asset over the benefit period of such asset; or to reflect consumption during the period of an asset that is not used in production.

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