Derivative Financial Instruments and Related Hedging Programs, Hedging Discussion (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2013 mmlbs	Dec. 31, 2012 mmlbs	Dec. 31, 2011 mmlbs	Dec. 31, 2013 2014 mmlbs	Dec. 31, 2013 2015 mmlbs	Mar. 29, 2010 Convertible Notes
Derivative Financial Instruments and Related Hedging Programs (Textuals) [Abstract]
Aggregate fair value of derivative instruments in a net liability position	$ (1.6)
Total fabricated products shipments containing fixed price terms	119.8	178.8	157.0
Firm price customer sales contracts containing price risk on anticipated purchases of primary aluminum				62.0	2.3
Principal amount of notes	$ 225.0	$ 225.0				$ 175.0