Cash and stock proceeds from sale of business.

No definition available.

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Data Type:	xbrli:monetaryItemType
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Period Type:	duration

- Definition

Shares of the company's stock received as consideration in the sale of a business unit.

+ References

No definition available.

+ Details

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- Definition

Pretax adjustment to an amount previously reported in discontinued operations that is directly related to the disposal of the component in a prior period. Examples of circumstances leading to such adjustments include the resolution of contingencies relating to the terms of the disposal transaction or relating to the operations of the component prior to its disposal, and the settlement of certain employee benefit plan obligations.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 205

-SubTopic 20

-Section 45

-Paragraph 4

-URI http://asc.fasb.org/extlink&oid=6892542&loc=d3e1012-107759

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 205

-SubTopic 20

-Section 50

-Paragraph 5

-URI http://asc.fasb.org/extlink&oid=6360339&loc=d3e1510-107760

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 205

-SubTopic 20

-Section 45

-Paragraph 5

-URI http://asc.fasb.org/extlink&oid=6892542&loc=d3e1020-107759

+ Details

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Data Type:	xbrli:monetaryItemType
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- Definition

Adjustment, net of tax, to an amount previously reported in discontinued operations that is directly related to the disposal of the component in a prior period. Examples of circumstances leading to such adjustments include the resolution of contingencies relating to the terms of the disposal transaction or relating to the operations of the component prior to its disposal, and the settlement of certain employee benefit plan obligations.

+ References

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Amount of operating income or loss attributable to the disposal group, including a component of the entity (discontinued operation), during the reporting period.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 205

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (c)

-URI http://asc.fasb.org/extlink&oid=6360339&loc=d3e1361-107760

+ Details

Name:	us-gaap_DisposalGroupIncludingDiscontinuedOperationOperatingIncomeLoss
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Amount of sales or other form of revenues attributable to the disposal group, including a component of the entity (discontinued operation), during the reporting period.

+ References

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Details

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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

The cash inflow associated with the amount received from the sale of a portion of the company's business, for example a segment, division, branch or other business, during the period.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Investing Activities

-URI http://asc.fasb.org/extlink&oid=6516133

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 12

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3179-108585

+ Details

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Balance Type:	debit
Period Type:	duration

Discontinued Operations (Details) (USD $) In Millions, except Share data, unless otherwise specified	3 Months Ended	9 Months Ended	0 Months Ended		3 Months Ended		9 Months Ended
	Sep. 30, 2012	Sep. 30, 2012	Nov. 20, 2012 Falling Springs [Member]	Feb. 12, 2008 Aluminum Extrusions Canada Business [Member]	Sep. 30, 2013 Aluminum Extrusions Canada Business [Member]	Sep. 30, 2012 Aluminum Extrusions Canada Business [Member]	Sep. 30, 2013 Aluminum Extrusions Canada Business [Member]	Sep. 30, 2012 Aluminum Extrusions Canada Business [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Proceeds from sale of membership interests			$ 16.6
Proceeds from sale of business			12.8	25.0
Common stock received from sale of membership interests			209,576
Sales reclassified to discontinued operations	2.2	3.0
Net income reclassified to discontinued operations	0.3	0.3
Charges for indemnifications under the purchase agreement related to environmental matters					(0.5)	(7.1)	(14.0)	(11.9)
Charges for indemnifications under the purchase agreement related to environmental matters, net of tax					$ (0.5)	$ (7.1)	$ (14.0)	$ (11.9)