Segment Reporting (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2012	Sep. 30, 2011
Summary of segment information
Net Sales	$ 304,039	$ 294,860	$ 996,347	$ 850,216
Operating (loss) income	12,548	3,173	40,015	9,572
Capital Expenditures	4,032	3,417	8,123	8,236
Depreciation and Amortization	6,263	4,861	19,350	14,919
Metals Segment [Member]
Summary of segment information
Net Sales	272,445	264,368	901,581	761,213
Operating (loss) income	14,488	4,298	46,251	12,979
Capital Expenditures	3,232	2,919	6,552	6,862
Depreciation and Amortization	5,912	4,619	18,335	14,041
Plastics Segment [Member]
Summary of segment information
Net Sales	31,594	30,492	94,766	89,003
Operating (loss) income	1,011	1,039	2,612	2,663
Capital Expenditures	800	498	1,571	1,374
Depreciation and Amortization	351	242	1,015	878
Other [Member]
Summary of segment information
Operating (loss) income	$ (2,951)	$ (2,164)	$ (8,848)	$ (6,070)