GOODWILL AND INTANGIBLE ASSETS (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Dec. 28, 2019	Dec. 29, 2018	Dec. 28, 2019	Dec. 29, 2018	Dec. 30, 2017
Components of amortized intangible assets
Gross Carrying Amount	$ 269,748	$ 251,141	$ 269,748	$ 251,141
Accumulated Amortization	163,113	143,908	163,113	143,908
Amortization expense for intangible assets	18,087	15,328			$ 15,911
Estimated Amortization Expense
2020	17,343		17,343
2021	15,298		15,298
2022	13,120		13,120
2023	11,345		11,345
2024	9,434		9,434
Customer Relationships
Components of amortized intangible assets
Gross Carrying Amount	237,626	219,508	237,626	219,508
Accumulated Amortization	149,720	132,180	$ 149,720	$ 132,180
Weighted Average Life			13 years	13 years
Patents & Proprietary Technology
Components of amortized intangible assets
Gross Carrying Amount	24,068	23,662	$ 24,068	$ 23,662
Accumulated Amortization	6,358	4,837	$ 6,358	$ 4,837
Weighted Average Life			14 years	14 years
Other
Components of amortized intangible assets
Gross Carrying Amount	8,054	7,971	$ 8,054	$ 7,971
Accumulated Amortization	$ 7,035	$ 6,891	$ 7,035	$ 6,891
Weighted Average Life			5 years	5 years

The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

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Useful life of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Accumulated amount of amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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Amount of amortization expense for assets, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized during the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of amortization expense for assets, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized during the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of amortization expense for assets, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized during the fourth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of amortization expense for assets, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized during the third fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of amortization expense for assets, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized during the second fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount before amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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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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