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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GOODWILL AND INTANGIBLE ASSETS - Amortized Intangible Assets - (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 24, 2022	Sep. 25, 2021	Sep. 24, 2022	Sep. 25, 2021	Dec. 25, 2021
Components of amortized intangible assets
Gross Carrying Amount	$ 305,516		$ 305,516		$ 290,680
Accumulated Amortization	185,102		185,102		178,723
Amortization expense for intangible assets	5,386	$ 6,137	16,766	$ 15,551
Estimated amortization expense
2022	22,021		22,021
2023	20,631		20,631
2024	18,703		18,703
2025	17,269		17,269
2026	12,743		12,743
Customer Relationships
Components of amortized intangible assets
Gross Carrying Amount	241,049		241,049		224,597
Accumulated Amortization	160,896		$ 160,896		$ 160,626
Weighted Average Life			13 years		13 years
Patents & Proprietary Technology
Components of amortized intangible assets
Gross Carrying Amount	57,202		$ 57,202		$ 58,699
Accumulated Amortization	19,572		$ 19,572		$ 13,955
Weighted Average Life			8 years		9 years
Trade Names
Components of amortized intangible assets
Gross Carrying Amount	2,850		$ 2,850		$ 2,850
Accumulated Amortization	543		$ 543		$ 183
Weighted Average Life			7 years		7 years
Other
Components of amortized intangible assets
Gross Carrying Amount	4,415		$ 4,415		$ 4,534
Accumulated Amortization	$ 4,091		$ 4,091		$ 3,959
Weighted Average Life			6 years		6 years