Note 16 - Segment Information - Segment Reporting Information by Revenue (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Net sales	$ 384,230	$ 456,976	$ 1,259,300	$ 1,285,491
Depreciation and amortization	4,642	4,200	14,209	12,857
Operating income	3,581	18,614	15,595	55,278
Other income (loss), net	12	17	(33)	(122)
Income before interest and income taxes	3,593	18,631	15,562	55,156
Interest and other expense on debt	2,569	2,923	8,985	7,579
Income before income taxes	1,024	15,708	6,577	47,577
Carbon Flat Products [Member]
Net sales	215,515	282,810	749,921	802,995
Depreciation and amortization	2,850	2,524	8,624	7,665
Operating income	(2,301)	14,493	(603)	40,901
Specialty Metals Flat Products [Member]
Net sales	97,563	92,153	281,718	255,037
Depreciation and amortization	441	341	1,403	880
Operating income	4,060	4,954	10,272	13,493
Tubular and Pipe Products [Member]
Net sales	71,152	82,013	227,661	227,459
Depreciation and amortization	1,309	1,311	4,056	4,237
Operating income	4,462	3,102	14,553	11,917
Corporate Segment [Member]
Depreciation and amortization	42	24	126	75
Operating income	$ (2,640)	$ (3,935)	$ (8,627)	$ (11,033)

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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