Goodwill and Intangible Assets Goodwill (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012
Changes in carrying amounts of goodwill
Beginning Goodwill	$ 130,517	$ 130,118
Accumulated impairment losses	(60,217)	(60,217)
Balance	70,300	69,901
Currency valuation	(1,011)	399
Ending Goodwill	129,506	130,517
Accumulated impairment losses	(60,217)	(60,217)
Balance	69,289	70,300
Goodwill, Impairment Loss	0
Metals Segment
Changes in carrying amounts of goodwill
Beginning Goodwill	117,544	117,145
Accumulated impairment losses	(60,217)	(60,217)
Balance	57,327	56,928
Currency valuation	(1,011)	399
Ending Goodwill	116,533	117,544
Accumulated impairment losses	(60,217)	(60,217)
Balance	56,316	57,327
Plastics Segment
Changes in carrying amounts of goodwill
Beginning Goodwill	12,973	12,973
Accumulated impairment losses	0	0
Balance	12,973	12,973
Currency valuation	0	0
Ending Goodwill	12,973	12,973
Accumulated impairment losses	0	0
Balance	$ 12,973	$ 12,973