Goodwill and Intangible Assets, Amortization Table (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
Mar. 31, 2012	Mar. 31, 2011
Goodwill and Intangible Assets (Textuals) [Abstract]
Amortization expense related to definite-lived intangible assets recorded in Fabricated products Segment	$ 0.4	$ 0.6
Expected amortization of intangible assets for the next five years
2012	1.4
2013	1.7
2014	1.6
2015	1.6
2016	1.6
Thereafter	28.9
Total	$ 36.8

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Aggregate amount of intangible asset amortization recognized as expense during the period.

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The aggregate estimated amortization expense for succeeding fiscal years for intangible assets subject to amortization.

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The amount of amortization expense expected to be recognized for the remainder of the finite-lived intangible asset useful life after the fifth succeeding fiscal year.

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The amount of amortization expense expected to be recognized during year five of the five succeeding fiscal years.

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The amount of amortization expense expected to be recognized during year four of the five succeeding fiscal years.

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The amount of amortization expense expected to be recognized during year one of the five succeeding fiscal years.

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The amount of amortization expense expected to be recognized during year three of the five succeeding fiscal years.

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The amount of amortization expense expected to be recognized during year two of the five succeeding fiscal years.

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