Segment Information (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2011 Lawsuit Segment Complaint	Sep. 30, 2010	Dec. 31, 2010
Segment Information
Number of reporting segments			3
Segment Reporting Information
Net Sales, External	$ 1,915,519	$ 1,488,150	$ 5,768,926	$ 4,515,979
Net Sales, External Non-U.S.	127,936	96,014	370,229	256,774
Total net sales	2,043,455	1,584,164	6,139,155	4,772,753
Operating income (loss)	108,785	69,000	502,330	317,932
Income (loss) before income taxes	67,606	30,929	383,305	205,500
Depreciation and amortization	55,962	57,278	166,965	168,948
Capital expenditures	38,126	24,224	91,795	95,868
Assets	6,003,481	5,610,459	6,003,481	5,610,459	5,589,934
Liabilities	3,656,451	3,506,783	3,656,451	3,506,783
Steel Operations
Segment Reporting Information
Net Sales, External	1,183,665	938,162	3,551,626	2,835,969
Net Sales, External Non-U.S.	44,345	21,509	138,723	72,906
Net Sales, Other segments	49,854	40,715	163,991	123,936
Total net sales	1,277,864	1,000,386	3,854,340	3,032,811
Operating income (loss)	136,194	85,201	543,117	351,085
Income (loss) before income taxes	114,805	65,666	480,296	295,332
Depreciation and amortization	27,320	28,596	82,164	84,894
Capital expenditures	10,457	10,530	28,891	39,747
Assets	2,629,873	2,513,562	2,629,873	2,513,562
Liabilities	488,476	414,455	488,476	414,455
Metals Recycling and Ferrous Resources Operations
Segment Reporting Information
Net Sales, External	624,742	484,605	1,944,928	1,497,542
Net Sales, External Non-U.S.	83,296	74,265	230,954	183,317
Net Sales, Other segments	351,219	245,810	1,069,661	728,491
Total net sales	1,059,257	804,680	3,245,543	2,409,350
Operating income (loss)	(3,388)	1,077	39,987	32,150
Income (loss) before income taxes	(14,697)	(9,588)	8,033	(3,413)
Depreciation and amortization	25,164	26,224	75,784	76,351
Capital expenditures	26,575	10,145	58,458	41,503
Assets	2,557,147	2,476,032	2,557,147	2,476,032
Liabilities	531,827	609,779	531,827	609,779
Steel Fabrication Operations
Segment Reporting Information
Net Sales, External	83,094	53,723	197,112	119,949
Net Sales, Other segments	16	197	612	236
Total net sales	83,110	53,920	197,724	120,185
Operating income (loss)	(246)	(494)	(4,764)	(11,787)
Income (loss) before income taxes	(2,139)	(1,919)	(9,918)	(15,696)
Depreciation and amortization	1,847	1,404	4,969	4,516
Capital expenditures	503		1,454	150
Assets	234,452	198,314	234,452	198,314
Liabilities	16,820	20,423	16,820	20,423
Other
Segment Reporting Information
Net Sales, External	24,018	11,660	75,260	62,519
Net Sales, External Non-U.S.	295	240	552	551
Net Sales, Other segments	3,033	2,463	8,452	7,182
Total net sales	27,346	14,363	84,264	70,252
Operating income (loss)	(28,437)	(14,781)	(78,115)	(50,476)
Income (loss) before income taxes	(35,025)	(21,147)	(97,105)	(66,886)
Depreciation and amortization	1,682	1,105	4,201	3,323
Capital expenditures	591	3,549	2,992	15,106
Assets	757,275	718,304	757,275	718,304
Liabilities	2,785,613	2,749,747	2,785,613	2,749,747
Eliminations
Segment Reporting Information
Net Sales, Other segments	(404,122)	(289,185)	(1,242,716)	(859,845)
Total net sales	(404,122)	(289,185)	(1,242,716)	(859,845)
Operating income (loss)	4,662	(2,003)	2,105	(3,040)
Income (loss) before income taxes	4,662	(2,083)	1,999	(3,837)
Depreciation and amortization	(51)	(51)	(153)	(136)
Capital expenditures				(638)
Assets	(175,266)	(295,753)	(175,266)	(295,753)
Liabilities	$ (166,285)	$ (287,621)	$ (166,285)	$ (287,621)