GOODWILL AND INTANGIBLE ASSETS - Amortized Intangible Assets (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Dec. 25, 2021	Dec. 25, 2021	Dec. 26, 2020	Dec. 28, 2019
Components of amortized intangible assets
Gross Carrying Amount	$ 290,680	$ 290,680	$ 271,042
Accumulated Amortization	178,723	178,723	170,847
Amortization expense for intangible assets		21,320	18,147	$ 18,087
Estimated Amortization Expense
2022	19,466	19,466
2023	17,692	17,692
2024	15,768	15,768
2025	14,301	14,301
2026	10,123	10,123
Customer Relationships
Components of amortized intangible assets
Gross Carrying Amount	224,597	224,597	237,232
Accumulated Amortization	160,626	$ 160,626	$ 155,760
Weighted Average Life		13 years	13 years
Impairment charge for intangible assets	4,483
Patents & Proprietary Technology
Components of amortized intangible assets
Gross Carrying Amount	58,699	$ 58,699	$ 26,208
Accumulated Amortization	13,955	$ 13,955	$ 8,301
Weighted Average Life		9 years	14 years
Trade Name
Components of amortized intangible assets
Gross Carrying Amount	2,850	$ 2,850
Accumulated Amortization	183	$ 183
Weighted Average Life		7 years
Other
Components of amortized intangible assets
Gross Carrying Amount	4,534	$ 4,534	$ 7,602
Accumulated Amortization	$ 3,959	$ 3,959	$ 6,786
Weighted Average Life		6 years	4 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 for assets, excluding financial assets and goodwill, lacking physical substance with finite life expected to be recognized in next fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of amortization for assets, excluding financial assets and goodwill, lacking physical substance with finite life expected to be recognized in fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of amortization for assets, excluding financial assets and goodwill, lacking physical substance with finite life expected to be recognized in fourth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of amortization for assets, excluding financial assets and goodwill, lacking physical substance with finite life expected to be recognized in third fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of amortization for assets, excluding financial assets and goodwill, lacking physical substance with finite life expected to be recognized in second fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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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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The amount of impairment loss recognized in the period resulting from the write-down of the carrying amount of a finite-lived intangible asset to fair value.

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