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REVENUES - General Information (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 29, 2024	Mar. 31, 2023	Dec. 29, 2023
Revenue
Payroll taxes, bonuses and employee benefit costs for all Company personnel	$ 26,509	$ 22,385
Revenue of the entity recorded in which it acts solely in the capacity of an agent	0
Retained accounts receivable	$ 16,100		$ 14,300
Maximum
Revenue
Percent of revenue (as a percent)	3.00%
Minimum
Revenue
Percent of revenue (as a percent)	2.00%
Cost of Sales
Revenue
Payroll taxes, bonuses and employee benefit costs for all Company personnel	$ 0
Allocation of facilities costs to contract revenue	$ 0