ACQUISITIONS AND DECONSOLIDATION (Tables)	12 Months Ended
Dec. 30, 2017
Pro forma results of operations
Valmont SM
Summary of fair values of the assets acquired and liabilities assumed
Summary of the major classes of acquired intangible assets and the respective weighted-average amortization periods
Shakespeare
Summary of fair values of the assets acquired and liabilities assumed
Summary of the major classes of acquired intangible assets and the respective weighted-average amortization periods

Tabular disclosure of pro forma results of operations for a material business acquisition or series of individually immaterial business acquisitions that are material in the aggregate.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (h)(2)-(3)
-URI http://asc.fasb.org/extlink&oid=65885119&loc=d3e1392-128463

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- Definition

Tabular disclosure of finite-lived and indefinite-lived intangible assets acquired as part of a business combination.

+ References

No definition available.

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- Definition

Tabular disclosure of the amounts recognized as of the acquisition date for each major class of assets acquired and liabilities assumed. May include but not limited to the following: (a) acquired receivables; (b) contingencies recognized at the acquisition date; and (c) the fair value of noncontrolling interests in the acquiree.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 20
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=73530397&loc=d3e4845-128472

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