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GOODWILL AND INTANGIBLE ASSETS (Details 5) - USD ($) $ in Thousands | 3 Months Ended | 12 Months Ended
--- | --- | ---
Sep. 29, 2018 | Dec. 29, 2018 | Dec. 30, 2017
Goodwill [Line Items] |  |  |
Goodwill impairment | $ 14,355 | $ 14,355 | $ 34,892
Engineered Support Structures |  |  |
Goodwill [Line Items] |  |  |
Goodwill impairment |  | 0 | 18,670
Coatings |  |  |
Goodwill [Line Items] |  |  |
Goodwill impairment |  | $ 0 | $ 16,222
Webforge |  |  |
Goodwill [Line Items] |  |  |
Impairment of intangible assets | $ 1,425 |  |

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