The revenues derived from sales of oil or gas in each geographic area during the reporting period divided by the number of barrels of oil produced or thousands of cubic feet of gas produced.

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GOODWILL AND INTANGIBLE ASSETS (Details 5) $ in Thousands	1 Months Ended	3 Months Ended			12 Months Ended
GOODWILL AND INTANGIBLE ASSETS (Details 5) $ in Thousands	Dec. 26, 2015 $ / bbl	Dec. 26, 2015 USD ($)	Sep. 26, 2015 USD ($)	Jun. 27, 2015 USD ($)	Dec. 26, 2015 USD ($) $ / bbl
Goodwill [Line Items]
Impairment of intangible assets		$ 19,600
Divestiture of business					$ 1,737
Goodwill impairment		7,100			$ 34,892
Average sales price of oil (in dollars per barrel) \| $ / bbl	40
Maximum
Goodwill [Line Items]
Estimated future sales price of oil (in dollars per barrel) \| $ / bbl					50
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		7,122	$ 9,100		16,222
Energy and Mining Segment
Goodwill [Line Items]
Divestiture of business					0
Goodwill impairment		18,670,000			$ 18,670
Webforge \| Engineered Support Structures
Goodwill [Line Items]
Impairment of intangible assets		$ 830	5,000
Industrial Galvanizers \| Coatings
Goodwill [Line Items]
Impairment of intangible assets			$ 1,100