Segment Information (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2013 segment	Mar. 31, 2012	Dec. 31, 2012
Segment Information
Number of reporting segments	3
Segment Reporting Information
Net Sales, External	$ 1,681,974	$ 1,865,670
Net Sales, External Non-U.S.	113,722	116,370
Total net sales	1,795,696	1,982,040
Operating income (loss)	96,232	119,816
Income (loss) before income taxes	62,649	68,456
Depreciation and amortization	57,061	55,572
Capital expenditures	45,346	45,555
Assets	5,956,574	6,043,627	5,815,416
Liabilities	3,450,570	3,637,142
Steel Operations
Segment Reporting Information
Net Sales, External	1,011,195	1,135,912
Net Sales, External Non-U.S.	50,117	50,808
Net Sales, Other segments	61,048	47,759
Total net sales	1,122,360	1,234,479
Operating income (loss)	119,301	137,308
Income (loss) before income taxes	105,007	119,078
Depreciation and amortization	26,387	26,084
Capital expenditures	24,726	5,948
Assets	2,566,642	2,677,623
Liabilities	557,404	494,177
Metals Recycling and Ferrous Resources Operations
Segment Reporting Information
Net Sales, External	557,611	634,134
Net Sales, External Non-U.S.	63,517	65,466
Net Sales, Other segments	276,364	411,520
Total net sales	897,492	1,111,120
Operating income (loss)	(9,824)	4,163
Income (loss) before income taxes	(17,854)	(4,273)
Depreciation and amortization	27,136	26,074
Capital expenditures	19,069	37,906
Assets	2,529,951	2,610,476
Liabilities	526,457	574,598
Steel Fabrication Operations
Segment Reporting Information
Net Sales, External	93,797	74,892
Net Sales, Other segments	578	4
Total net sales	94,375	74,896
Operating income (loss)	1,530	(2,668)
Income (loss) before income taxes	(76)	(4,184)
Depreciation and amortization	2,057	1,848
Capital expenditures	881	1,168
Assets	254,176	231,284
Liabilities	15,646	14,542
Other
Segment Reporting Information
Net Sales, External	19,371	20,732
Net Sales, External Non-U.S.	88	96
Net Sales, Other segments	5,395	3,262
Total net sales	24,854	24,090
Operating income (loss)	(16,439)	(16,862)
Income (loss) before income taxes	(26,092)	(40,040)
Depreciation and amortization	1,532	1,617
Capital expenditures	670	533
Assets	822,064	712,673
Liabilities	2,556,590	2,732,432
Eliminations
Segment Reporting Information
Net Sales, Other segments	(343,385)	(462,545)
Total net sales	(343,385)	(462,545)
Operating income (loss)	1,664	(2,125)
Income (loss) before income taxes	1,664	(2,125)
Depreciation and amortization	(51)	(51)
Assets	(216,259)	(188,429)
Liabilities	$ (205,527)	$ (178,607)