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GOODWILL AND INTANGIBLE ASSETS - Carrying Values of Trade Names - (Details) - USD ($) $ in Thousands | Jun. 30, 2018 | Dec. 30, 2017
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Valmont SM |  |
Non-amortized intangible assets |  |
Carrying value of trade names | $ 9,717 | $ 9,973
Webforge |  |
Non-amortized intangible assets |  |
Carrying value of trade names | 9,230 | 9,432
Ingal EPS/Ingal Civil Products |  |
Non-amortized intangible assets |  |
Carrying value of trade names | 7,526 | 7,690
Shakespeare |  |
Non-amortized intangible assets |  |
Carrying value of trade names | 4,000 | 4,000
Other |  |
Non-amortized intangible assets |  |
Carrying value of trade names | $ 16,894 | $ 22,647

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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
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- Definition Amount of assets, excluding financial assets and goodwill, lacking physical substance and having a projected indefinite period of benefit. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 30 -Section 50 -Paragraph 2 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16323-109275 + Details
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