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Income Taxes (Narrative) (Details) - USD ($)	12 Months Ended
	Dec. 25, 2019	Dec. 26, 2018	Dec. 27, 2017
Valuation Allowance [Line Items]
Net tax benefit recognized related to the Tax Act			$ 1,600,000
Tax benefit recognized related to share-based compensation	$ 2,000,000.0	$ 1,400,000	1,700,000
Liability for income tax examination	2,000,000.0
Net operating loss carryforwards - state	9,621,000	13,899,000
Increase (decrease) of tax valuation allowance	(2,935,000)	121,000	$ 216,000
Valuation allowance	10,264,000	13,199,000
Interest and penalties recognized on unrecognized tax benefits	0	$ 0
South Carolina NOL Carryforwards
Valuation Allowance [Line Items]
Net operating loss carryforwards - state	8,300,000
Increase (decrease) of tax valuation allowance	3,600,000
Valuation allowance	8,100,000
State Enterprise Zone Credits
Valuation Allowance [Line Items]
Increase (decrease) of tax valuation allowance	(700,000)
Valuation allowance	1,100,000
Foreign Tax Credit Carryforward
Valuation Allowance [Line Items]
Valuation allowance	$ 700,000

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible state and local operating loss carryforwards.

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