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 - Amortizing Intangible Assets (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 24, 2022	Sep. 30, 2023	Sep. 24, 2022	Dec. 31, 2022
Components of amortized intangible assets
Weighted Average Life	4 years		4 years		4 years
Amortization expense for intangible assets	$ 5,191	$ 5,386	$ 15,606	$ 16,766
Estimated Amortization Expense
Remainder of 2023	10,122		10,122
2024	10,122		10,122
2025	10,122		10,122
2026	10,122		10,122
2027	10,122		10,122
2028	10,122		10,122
Customer relationships
Components of amortized intangible assets
Gross Carrying Amount	219,467		219,467		$ 222,716
Accumulated Amortization	152,718		152,718		145,502
Patents & Proprietary Technology
Components of amortized intangible assets
Gross Carrying Amount	58,439		58,439		58,404
Accumulated Amortization	44,673		44,673		21,291
Trade names
Components of amortized intangible assets
Gross Carrying Amount	2,870		2,870		2,850
Accumulated Amortization	952		952		645
Other
Components of amortized intangible assets
Gross Carrying Amount	4,676		4,676		2,462
Accumulated Amortization	$ 4,393		$ 4,393		$ 2,164