Goodwill and Intangible Assets, Amortization Table (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Expected amortization of intangible assets for the next five years
2013	$ 1.7
2014	1.6
2015	1.6
2016	1.6
2017	1.6
Thereafter	27.3
Total	35.4	37.2
Amortization expense related to definite-lived intangible assets recorded in Fabricated products Segment	$ 1.8	$ 2.2	$ 0.3