Business Segments (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended	9 Months Ended
Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Segment Reporting Information [Line Items]
Total sales:	$ 996.8	$ 1,164.9	$ 3,205.7	$ 3,750.5
Intersegment sales:	24.4	33.4	77.5	105.0
Sales to external customers:	972.4	1,131.5	3,128.2	3,645.5
Operating profit (loss):	27.6	113.5	175.3	422.2
Corporate expenses	(8.1)	(14.9)	(32.3)	(52.4)
Interest expense, net	(18.2)	(17.2)	(46.5)	(55.7)
Closed company and other expenses	(2.1)	(2.7)	(11.0)	(14.8)
Retirement benefit expense	(34.5)	(30.6)	(99.5)	(91.8)
Income (loss) before income taxes	(35.3)	48.1	(14.0)	207.5
Interest Costs Capitalized	12.7	6.6
High Performance Metals
Segment Reporting Information [Line Items]
Total sales:	481.2	591.8	1,561.7	1,858.0
Intersegment sales:	17.3	21.2	53.6	69.1
Sales to external customers:	463.9	570.6	1,508.1	1,788.9
Operating profit (loss):	48.0	87.4	192.0	303.8
Flat-Rolled Products
Segment Reporting Information [Line Items]
Total sales:	515.6	573.1	1,644.0	1,892.5
Intersegment sales:	7.1	12.2	23.9	35.9
Sales to external customers:	508.5	560.9	1,620.1	1,856.6
Operating profit (loss):	$ (20.4)	$ 26.1	$ (16.7)	$ 118.4

corporate office expenses not allocable to business segments

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Net interest expense - the cost of borrowed funds as interest charged against earnings during the period net of interest income derived from investments in debt securities and on cash and cash equivalents.

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Other expense, net of gains on asset sales primarily includes charges incurred in connection with closed operations and other non-operating income or expense

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Represents defined benefit plan pension expense, and other postretirement benefit expense for both defined benefit and defined contribution plans

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- Definition

Business segment operating profit, which excludes costs for restructuring charges, retirement benefit income or expense, corproate expenses, interest expense, debt extinguishment costs and costs associated with closed operations. These costs are excluded for segment reporting to provide a profit measure based on what management considers to be controllable costs at the business segment level

+ References

No definition available.

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Sum of operating profit and nonoperating income or expense before Income or Loss from equity method investments, income taxes, extraordinary items, and noncontrolling interest.

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

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Amount of interest capitalized during the period.

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Aggregate revenue recognized during the period (derived from goods sold, services rendered, insurance premiums, or other activities that constitute an entity's earning process). For financial services companies, also includes investment and interest income, and sales and trading gains.

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Amount of revenue from transactions with other operating segments of the same entity.

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Amount of total revenue for the reportable segments, including revenue from external customers, transactions with other operating segments of the same entity, and (gross) interest revenue. All considered to be "operating revenue" for purposes of the taxonomy.

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