LEASES - Lease Cost (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 26, 2024	Jun. 28, 2023	Jun. 26, 2024	Jun. 28, 2023
Lessee, Lease, Description [Line Items]
Amortization of right-to-use assets	$ 67	$ 19	$ 86	$ 38
Interest on lease liabilities	12	10	27	21
Fixed rent cost	7,229	7,111	14,360	14,145
Short-term lease cost		1	1	4
Variable lease cost	497	333	977	708
Sublease income	(1,758)	(1,246)	(3,537)	(2,493)
Total lease cost	6,047	6,228	11,914	12,423
Occupancy and other operating expenses
Lessee, Lease, Description [Line Items]
Total lease cost	5,851	6,048	11,566	12,057
General & administrative
Lessee, Lease, Description [Line Items]
Total lease cost	117	133	235	269
Depreciation and amortization
Lessee, Lease, Description [Line Items]
Total lease cost	67	19	86	38
Interest expense
Lessee, Lease, Description [Line Items]
Total lease cost	12	10	27	21
Closed-store reserve
Lessee, Lease, Description [Line Items]
Total lease cost		18		38
Property Leases
Lessee, Lease, Description [Line Items]
Amortization of right-to-use assets	20	19	38	37
Interest on lease liabilities	8	10	19	20
Fixed rent cost	7,180	6,873	14,208	13,705
Variable lease cost	151	130	284	272
Sublease income	(1,758)	(1,246)	(3,537)	(2,493)
Total lease cost	5,601	5,786	11,012	11,541
Equipment Leases
Lessee, Lease, Description [Line Items]
Amortization of right-to-use assets	47		48	1
Interest on lease liabilities	4		8	1
Fixed rent cost	49	238	152	440
Short-term lease cost		1	1	4
Variable lease cost	346	203	693	436
Total lease cost	$ 446	$ 442	$ 902	$ 882