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		9 Months Ended		12 Months Ended
	Sep. 28, 2019	Sep. 29, 2018	Sep. 28, 2019	Sep. 29, 2018	Dec. 29, 2018
Components of amortized intangible assets
Gross Carrying Amount	$ 266,459		$ 266,459		$ 251,141
Accumulated Amortization	156,137		156,137		143,908
Amortization expense for intangible assets	4,484	$ 3,721	13,506	$ 11,176
Estimated amortization expense
2019	17,687		17,687
2020	17,821		17,821
2021	15,523		15,523
2022	13,286		13,286
2023	11,594		11,594
Customer Relationships
Components of amortized intangible assets
Gross Carrying Amount	236,029		236,029		219,508
Accumulated Amortization	143,306		$ 143,306		$ 132,180
Weighted Average Life			13 years		13 years
Patents & Proprietary Technology
Components of amortized intangible assets
Gross Carrying Amount	22,936		$ 22,936		$ 23,662
Accumulated Amortization	5,945		$ 5,945		$ 4,837
Weighted Average Life			14 years		14 years
Other
Components of amortized intangible assets
Gross Carrying Amount	7,494		$ 7,494		$ 7,971
Accumulated Amortization	$ 6,886		$ 6,886		$ 6,891
Weighted Average Life			5 years		5 years