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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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.

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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 INTANGIBLE ASSETS (Details 5) - USD ($) $ in Thousands	3 Months Ended			12 Months Ended
	Sep. 24, 2016	Jun. 25, 2016	Dec. 26, 2015	Dec. 26, 2015
Goodwill [Line Items]
Impairment of intangible assets			$ 19,600
Divestiture of business				$ (1,737)
Goodwill impairment			7,100	34,892
Engineered Support Structures
Goodwill [Line Items]
Divestiture of business		$ 1,737		(1,737)
Goodwill impairment				0
Coatings
Goodwill [Line Items]
Divestiture of business				0
Goodwill impairment				16,222
Energy and Mining Segment
Goodwill [Line Items]
Divestiture of business				0
Goodwill impairment			$ 19,000	$ 18,670
Webforge \| Engineered Support Structures
Goodwill [Line Items]
Impairment of intangible assets	$ 5,830
Industrial Galvanizers \| Coatings
Goodwill [Line Items]
Impairment of intangible assets	$ 1,100