Amount of gain (loss), before tax expense or benefit and not previously recognized, resulting from the sale of a business component.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 205

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-Section 45

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- Definition

A description of the facts and circumstances leading to the completed or expected disposal, and the manner and timing of that disposal. Sales of disposal groups, including those classified as components of the entity (discontinued operations), are generally expected to be completed within one year of their classification as held-for-sale.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 205

-SubTopic 20

-Section S99

-Paragraph 2

-Subparagraph (SAB TOPIC 5.Z.5 Q2)

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-Publisher SEC

-Name Staff Accounting Bulletin (SAB)

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- Definition

Amount of divestiture of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

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- Definition

This element represents the cash inflow during the period from the sale of a component of the entity.

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

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-Name Accounting Standards Codification

-Glossary Investing Activities

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Discontinued Operations (Narrative) (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended	0 Months Ended
	Dec. 31, 2012	Jun. 04, 2012	Aug. 30, 2012
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Discontinued Operation, Gain (Loss) from Disposal of Discontinued Operation, before Income Tax	$ 3,193
Shipping Systems Division [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Disposal Group, Including Discontinued Operation, Description and Timing of Disposal		On June 4, 2012, the Company sold substantially all of the assets and liabilities of its railway securement business, Shipping Systems Division (SSD)
Proceeds from Divestiture of Businesses, Net of Cash Divested		8,579
Discontinued Operation, Gain (Loss) from Disposal of Discontinued Operation, before Income Tax		3,508
Goodwill, Written off Related to Sale of Business Unit	2,588
Precise Structural Products Business [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Disposal Group, Including Discontinued Operation, Description and Timing of Disposal			On August 30, 2012, the Company sold substantially all of the assets and liabilities of its precise structural products business
Proceeds from Divestiture of Businesses, Net of Cash Divested			2,643
Discontinued Operation, Gain (Loss) from Disposal of Discontinued Operation, before Income Tax			$ (315)