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REVENUES - General Information (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 27, 2024	Sep. 29, 2023	Sep. 27, 2024	Sep. 29, 2023	Dec. 29, 2023
Revenue
Payroll taxes, bonuses and employee benefit costs for all Company personnel	$ 25,876	$ 23,805	$ 78,449	$ 68,606
Revenue of the entity recorded in which it acts solely in the capacity of an agent			0
Retained accounts receivable	$ 18,900		$ 18,900		$ 14,300
Minimum
Revenue
Percent of revenue (as a percent)	2.00%		2.00%
Maximum
Revenue
Percent of revenue (as a percent)	3.00%		3.00%
Cost of Sales
Revenue
Payroll taxes, bonuses and employee benefit costs for all Company personnel			$ 0
Allocation of facilities costs to contract revenue			$ 0