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.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 50
-Paragraph 3
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16373-109275

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=121586364&loc=d3e3602-108585

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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.

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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

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Number of Trade Names Impaired

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GOODWILL AND INTANGIBLE ASSETS - Carrying Values of Trade Names - (Details)	3 Months Ended
	Jun. 27, 2020 USD ($) numberOfTradeNames	Sep. 28, 2019 USD ($)	Dec. 28, 2019 USD ($)
Non-amortized intangible assets
Number of trade names impaired \| numberOfTradeNames	2
Newmark
Non-amortized intangible assets
Carrying value of trade names	$ 11,111,000		$ 11,111,000
Webforge
Non-amortized intangible assets
Carrying value of trade names	7,250,000		9,143,000
Convert Italia S.p.A
Non-amortized intangible assets
Carrying value of trade names	8,412,000		8,378,000
Valmont SM
Non-amortized intangible assets
Carrying value of trade names	8,010,000		7,966,000
Ingal EPS/Ingal Civil Products
Non-amortized intangible assets
Carrying value of trade names	7,029,000		7,454,000
Walpar
Non-amortized intangible assets
Carrying value of trade names	3,500,000		3,500,000
Shakespeare
Non-amortized intangible assets
Carrying value of trade names	4,000,000		4,000,000
Other
Non-amortized intangible assets
Carrying value of trade names	14,570,000		17,555,000
Trade Names
Non-amortized intangible assets
Carrying value of trade names	63,882,000		$ 69,107,000
Impairment indefinite-lived intangible assets	$ 3,900,000	$ 0