Segment Reporting - Information by Reportable Segment (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended				6 Months Ended
	Jun. 30, 2013		Jun. 30, 2012		Jun. 30, 2013		Jun. 30, 2012
Summary of segment information
Net Sales	$ 273,410		$ 329,392		$ 566,124		$ 692,308
Operating (loss) income	(3,763)		9,560		(4,736)		27,716
Capital Expenditures	3,829		2,038		5,436		4,091
Depreciation and amortization	6,633		6,474		13,204		13,087
Metals segment
Summary of segment information
Net Sales	239,450		297,244		497,830		629,136
Operating (loss) income	(2,576)		11,901		(2,851)		32,012
Capital Expenditures	3,520		1,668		4,647		3,320
Depreciation and amortization	6,211		6,117		12,376		12,423
Plastics segment
Summary of segment information
Net Sales	33,960		32,148		68,294		63,172
Operating (loss) income	720		1,064		1,901		1,601
Capital Expenditures	309		370		789		771
Depreciation and amortization	422		357		828		664
Other
Summary of segment information
Net Sales	0	[1]	0	[1]	0	[1]	0	[1]
Operating (loss) income	(1,907)	[1]	(3,405)	[1]	(3,786)	[1]	(5,897)	[1]
Capital Expenditures	0	[1]	0	[1]	0	[1]	0	[1]
Depreciation and amortization	$ 0	[1]	$ 0	[1]	$ 0	[1]	$ 0	[1]

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