Goodwill and Intangible Assets Goodwill (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended		12 Months Ended
	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014	Dec. 31, 2014
Changes in carrying amounts of goodwill
Beginning Goodwill Gross		$ 129,350
Accumulated impairment losses		(116,377)		$ (116,377)
Goodwill Net Beginning Balance		12,973
Goodwill, Impairment Loss	$ 0	0	$ (56,160)
Ending Goodwill Gross		129,350		129,350
Goodwill Net Ending Balance		12,973		12,973
Metals Segment [Member]
Changes in carrying amounts of goodwill
Beginning Goodwill Gross		116,377
Accumulated impairment losses		(116,377)		(116,377)
Goodwill Net Beginning Balance		0
Ending Goodwill Gross		116,377		116,377
Goodwill Net Ending Balance		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