Leases - Lease Cost (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 29, 2021	Sep. 23, 2020	Sep. 29, 2021	Sep. 23, 2020
Lessee, Lease, Description [Line Items]
Amortization of right-to-use assets	$ 19		$ 62
Interest on lease liabilities	15	$ 5	46	$ 16
Operating Lease, Cost	6,819	6,799	20,796	20,488
Short-term Lease, Cost	7	6	17	18
Variable Lease, Cost	208	166	673	445
Sublease Income	(1,128)	(883)	(2,722)	(2,424)
Total lease cost	5,940	6,093	18,872	18,543
Occupancy and Other Operating Expenses
Lessee, Lease, Description [Line Items]
Total lease cost	5,811	5,786	18,191	17,582
General and Administrative Expense
Lessee, Lease, Description [Line Items]
Total lease cost	97	114	316	344
Depreciation and amortization
Lessee, Lease, Description [Line Items]
Total lease cost	18	5	60	16
Interest Expense
Lessee, Lease, Description [Line Items]
Total lease cost	14		44
Closed-store reserve
Lessee, Lease, Description [Line Items]
Total lease cost		188	261	601
Property Lease [Member]
Lessee, Lease, Description [Line Items]
Amortization of right-to-use assets	18		60
Interest on lease liabilities	14	5	44	16
Operating Lease, Cost	6,552	6,502	19,935	19,577
Variable Lease, Cost	138	116	413	325
Sublease Income	(1,128)	(883)	(2,722)	(2,424)
Total lease cost	5,594	5,740	17,730	17,494
Equipment Lease [Member]
Lessee, Lease, Description [Line Items]
Amortization of right-to-use assets	1		2
Interest on lease liabilities	1		2
Operating Lease, Cost	267	297	861	911
Short-term Lease, Cost	7	6	17	18
Variable Lease, Cost	70	50	260	120
Total lease cost	$ 346	$ 353	$ 1,142	$ 1,049