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. 27, 2020	Jun. 29, 2019	Jun. 27, 2020	Jun. 29, 2019	Dec. 28, 2019
Components of amortized intangible assets
Gross Carrying Amount	$ 262,081		$ 262,081		$ 269,748
Accumulated Amortization	156,219		156,219		163,113
Amortization expense for intangible assets	4,511	$ 4,632	9,103	$ 9,022
Estimated amortization expense
2020	17,214		17,214
2021	14,838		14,838
2022	12,959		12,959
2023	11,116		11,116
2024	9,389		9,389
Customer Relationships
Components of amortized intangible assets
Gross Carrying Amount	230,235		230,235		237,626
Accumulated Amortization	142,425		$ 142,425		$ 149,720
Weighted Average Life			13 years		13 years
Patents & Proprietary Technology
Components of amortized intangible assets
Gross Carrying Amount	24,484		$ 24,484		$ 24,068
Accumulated Amortization	7,190		$ 7,190		$ 6,358
Weighted Average Life			14 years		14 years
Other
Components of amortized intangible assets
Gross Carrying Amount	7,362		$ 7,362		$ 8,054
Accumulated Amortization	$ 6,604		$ 6,604		$ 7,035
Weighted Average Life			4 years		5 years