Amount of write-down of assets recognized in the income statement. Includes, but is not limited to, losses from tangible assets, intangible assets and goodwill.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 28

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3602-108585

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 360

-SubTopic 10

-Section 45

-Paragraph 4

-URI http://asc.fasb.org/extlink&oid=8077374&loc=d3e2420-110228

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The amount of expense recognized in the current period that reflects the allocation of the cost of tangible assets over the assets' useful lives. Includes production and non-production related depreciation.

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- Definition

Amount of interest capitalized, including amount of allowance for funds used during construction.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Allowance for Funds Used during Construction

-URI http://asc.fasb.org/extlink&oid=6504829

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 980

-SubTopic 835

-Section 45

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6501662&loc=d3e56162-110433

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Useful life of long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

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Summary of Significant Accounting Policies, Textuals, Property, Plant and Equipment (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Property, Plant and Equipment
Interest expense capitalized as construction in progress	$ 2.5	$ 3.4	$ 1.7
Depreciation expense	29.5us-gaap_Depreciation	26.4us-gaap_Depreciation	24.7us-gaap_Depreciation
Asset impairment charge	1.5us-gaap_AssetImpairmentCharges	0us-gaap_AssetImpairmentCharges	4.4us-gaap_AssetImpairmentCharges
Fabricated Products
Property, Plant and Equipment
Depreciation expense	29.0	25.8	24.2
Asset impairment charge	1.5		4.4
Fabricated Products \| Idled equipment
Property, Plant and Equipment
Asset impairment charge		$ 0
Minimum \| Land improvements
Property, Plant and Equipment
Property, plant and equipment useful lives (in years)	3 years
Minimum \| Buildings and leasehold improvements
Property, Plant and Equipment
Property, plant and equipment useful lives (in years)	15 years
Minimum \| Machinery and equipment
Property, Plant and Equipment
Property, plant and equipment useful lives (in years)	1 year
Minimum \| Capital lease assets
Property, Plant and Equipment
Property, plant and equipment useful lives (in years)	3 years
Maximum \| Land improvements
Property, Plant and Equipment
Property, plant and equipment useful lives (in years)	25 years
Maximum \| Buildings and leasehold improvements
Property, Plant and Equipment
Property, plant and equipment useful lives (in years)	45 years
Maximum \| Machinery and equipment
Property, Plant and Equipment
Property, plant and equipment useful lives (in years)	24 years
Maximum \| Capital lease assets
Property, Plant and Equipment
Property, plant and equipment useful lives (in years)	5 years