Goodwill and Intangible Assets Goodwill (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Mar. 31, 2015	Dec. 31, 2014
Changes in carrying amounts of goodwill
Beginning Goodwill Gross		$ 129,350us-gaap_GoodwillGross	$ 129,350us-gaap_GoodwillGross
Accumulated impairment losses		(116,377)	(116,377)
Goodwill Net Beginning Balance		12,973us-gaap_Goodwill	12,973us-gaap_Goodwill
Ending Goodwill Gross	129,350us-gaap_GoodwillGross	129,350us-gaap_GoodwillGross	129,350us-gaap_GoodwillGross
Goodwill Net Ending Balance	12,973us-gaap_Goodwill	12,973us-gaap_Goodwill	12,973us-gaap_Goodwill
Metals Segment [Member]
Changes in carrying amounts of goodwill
Beginning Goodwill Gross		116,377	116,377
Accumulated impairment losses		(116,377)	(116,377)
Goodwill Net Beginning Balance		0	0
Ending Goodwill Gross	116,377	116,377	116,377
Goodwill Net Ending Balance	0	0	0
Plastics Segment
Changes in carrying amounts of goodwill
Beginning Goodwill Gross		12,973
Accumulated impairment losses		0	0
Goodwill Net Beginning Balance		12,973
Goodwill, Impairment Loss	0
Ending Goodwill Gross	12,973	12,973
Goodwill Net Ending Balance	$ 12,973	$ 12,973

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 20

-Section 50

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Amount before accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

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Amount of loss from the write-down of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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-Publisher FASB

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