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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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