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			6 Months Ended
	Jun. 25, 2022	Mar. 26, 2022	Jun. 26, 2021	Jun. 25, 2022	Jun. 26, 2021	Dec. 25, 2021
Components of amortized intangible assets
Gross Carrying Amount	$ 312,479			$ 312,479		$ 290,680
Accumulated Amortization	185,909			185,909		178,723
Amortization expense for intangible assets	5,531		$ 5,182	11,380	$ 9,414
Estimated amortization expense
2022	21,425			21,425
2023	19,588			19,588
2024	17,675			17,675
2025	16,241			16,241
2026	15,823			15,823
Customer Relationships
Components of amortized intangible assets
Gross Carrying Amount	246,965			246,965		224,597
Accumulated Amortization	163,494			$ 163,494		160,626
Weighted Average Life		13 years		13 years
Patents & Proprietary Technology
Components of amortized intangible assets
Gross Carrying Amount	58,188			$ 58,188		58,699
Accumulated Amortization	17,861			$ 17,861		13,955
Weighted Average Life		9 years		9 years
Other
Components of amortized intangible assets
Gross Carrying Amount	4,476			$ 4,476		4,534
Accumulated Amortization	4,113			$ 4,113		3,959
Weighted Average Life		6 years		6 years
Trade Names
Components of amortized intangible assets
Gross Carrying Amount	2,850			$ 2,850		2,850
Accumulated Amortization	$ 441			$ 441		$ 183
Weighted Average Life		7 years		7 years