LEASES - Lease Cost (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jul. 03, 2021	Jun. 27, 2020	Jul. 03, 2021	Jun. 27, 2020
Leases [Abstract]
Operating lease costs	$ 2,612	$ 2,314	$ 5,076	$ 4,611
Finance lease cost - amortization of right-of-use assets	62	53	115	106
Finance lease cost - interest on lease liabilities	15	17	29	34
Short-term lease cost	97	49	155	104
Variable lease cost	1,116	816	1,848	1,654
Sublease income	(185)	(185)	(371)	(371)
Total lease cost	$ 3,717	$ 3,064	$ 6,852	$ 6,138
Weighted average remaining lease term:
Operating leases	5 years 8 months 12 days	6 years 7 months 17 days	5 years 8 months 12 days	6 years 7 months 17 days
Finance leases	4 years 10 months 2 days	4 years 2 months 4 days	4 years 10 months 2 days	4 years 2 months 4 days
Weighted average discount rate:
Operating leases	5.04%	6.62%	5.04%	6.62%
Finance leases	2.25%	6.24%	2.25%	6.24%