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Income Taxes - (Narrative) (Details) - USD ($)	12 Months Ended
	Dec. 30, 2020	Dec. 25, 2019	Dec. 26, 2018
Valuation Allowance [Line Items]
Net operating loss carryback	$ 900,000
Tax expense (benefit) recognized related to share-based compensation	1,000,000.0	$ (2,000,000.0)	$ (1,400,000)
Liability for income tax examination		2,000,000.0
Income tax refunds	2,100,000
Net operating loss carryforwards - state	5,888,000	9,621,000
Increase (decrease) of tax valuation allowance	(3,041,000)	(2,935,000)	$ 121,000
Valuation allowance	7,223,000	10,264,000
Interest and penalties recognized on unrecognized tax benefits	0	$ 0
South Carolina NOL Carryforwards
Valuation Allowance [Line Items]
Net operating loss carryforwards - state	4,600,000
Valuation allowance	4,400,000
State Enterprise Zone Credits
Valuation Allowance [Line Items]
Valuation allowance	1,500,000
Foreign Tax Credit Carryforward
Valuation Allowance [Line Items]
Valuation allowance	$ 300,000

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