LEASES - Components of Lease Expense (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Oct. 01, 2021	Sep. 25, 2020	Oct. 01, 2021	Sep. 25, 2020
Leases [Abstract]
Operating lease cost	$ 1,911	$ 1,873	$ 5,654	$ 6,556
Variable lease cost	467	681	1,494	2,183
Total lease cost	2,378	2,554	7,148	8,739
Cash payments	1,987	3,134	5,744	7,772
Right-of-use assets obtained in exchange for operating lease obligations	$ 194	$ 69	$ 5,670	$ 1,740