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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GOODWILL AND INTANGIBLE ASSETS - Amortized Intangible Assets - (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 26, 2021	Jun. 27, 2020	Jun. 26, 2021	Jun. 27, 2020	Dec. 26, 2020
Components of amortized intangible assets
Gross Carrying Amount	$ 312,378		$ 312,378		$ 271,042
Accumulated Amortization	181,500		181,500		170,847
Amortization expense for intangible assets	5,182	$ 4,511	9,414	$ 9,103
Estimated amortization expense
2021	21,159		21,159
2022	21,161		21,161
2023	19,324		19,324
2024	17,374		17,374
2025	15,929		15,929
Customer Relationships
Components of amortized intangible assets
Gross Carrying Amount	241,422		241,422		237,232
Accumulated Amortization	164,636		$ 164,636		$ 155,760
Weighted Average Life			13 years		13 years
Patents & Proprietary Technology
Components of amortized intangible assets
Gross Carrying Amount	63,413		$ 63,413		$ 26,208
Accumulated Amortization	10,023		$ 10,023		$ 8,301
Weighted Average Life			9 years		14 years
Other
Components of amortized intangible assets
Gross Carrying Amount	7,543		$ 7,543		$ 7,602
Accumulated Amortization	$ 6,841		$ 6,841		$ 6,786
Weighted Average Life			4 years		4 years