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.

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

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The amount of impairment loss recognized in the period resulting from the write-down of the carrying amount of a finite-lived intangible asset to fair value.

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Amount of impairment loss resulting from write-down of assets, excluding financial assets and goodwill, lacking physical substance and having a projected indefinite period of benefit to fair value.

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Goodwill And Other Intangible Assets (Narrative) (Details) - USD ($)	3 Months Ended		12 Months Ended
	Oct. 02, 2016	Oct. 04, 2015	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Indefinite-lived Intangible Assets by Segment [Line Items]
Impairment Charges			$ (208,000)	$ (460,000)
Impairment charges			208,000	2,502,000	$ 726,000
Impairment of Intangible Assets, Indefinite-lived (Excluding Goodwill)			0
Trademarks and Trade Names [Member]
Indefinite-lived Intangible Assets by Segment [Line Items]
Impairment Charges			0	$ (460,000)
Goodwill, impairment charges			$ 0
Energy [Member]
Indefinite-lived Intangible Assets by Segment [Line Items]
Goodwill, Written off Related to Sale of Business Unit					(425,000)
Aerospace [Member]
Indefinite-lived Intangible Assets by Segment [Line Items]
Goodwill, Written off Related to Sale of Business Unit					$ (301,000)
Patents [Member]
Indefinite-lived Intangible Assets by Segment [Line Items]
Impairment of Intangible Assets, Indefinite-lived (Excluding Goodwill)		$ 200,000
Trademarks [Member]
Indefinite-lived Intangible Assets by Segment [Line Items]
Impairment of Intangible Assets, Indefinite-lived (Excluding Goodwill)	$ 500,000