Income Taxes (Narrative) (Details) - USD ($) $ in Thousands	Dec. 26, 2018	Dec. 27, 2017
Valuation Allowance [Line Items]
Tax credit carryforward	$ 11,061	$ 13,355
Alternative minimum tax credit carryforwards	928	3,534
Valuation allowance	13,199	$ 13,078
General Business Tax Credit Carryforward [Member]
Valuation Allowance [Line Items]
Tax credit carryforward	7,400
South Carolina NOL Carryforwards [Member]
Valuation Allowance [Line Items]
Valuation allowance	$ 11,800

Amount before allocation of valuation allowances of deferred tax asset attributable to deductible alternative minimum tax credit carryforwards.

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