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Summary of Significant Accounting Policies (Details) - USD ($) $ in Thousands | 12 Months Ended |  |  |
--- | --- | --- | --- | ---
Dec. 26, 2018 | Dec. 27, 2017 | Dec. 27, 2018 | Dec. 28, 2017 | Dec. 29, 2016
Accounting Policies [Abstract] |  |  |  |  |
Short-term investments, included as cash and cash equivalents | $ 400 | $ 1,900 |  |  |
Discounted insurance liabilities | $ 17,000 | $ 16,900 |  |  |
Self insurance liabilities, discount rate | 2.50% | 2.00% |  |  |
Undiscounted insurance liabilities | $ 18,200 | $ 18,100 |  |  |
New Accounting Pronouncements or Change in Accounting Principle [Line Items] |  |  |  |  |
Cumulative effect adjustment |  |  |  | $ (15,446) | $ 9,139
(Deficit) [Member] |  |  |  |  |
New Accounting Pronouncements or Change in Accounting Principle [Line Items] |  |  |  |  |
Cumulative effect adjustment |  |  |  | $ 100 |
Estimated Forfeitures [Member] | (Deficit) [Member] |  |  |  |  |
New Accounting Pronouncements or Change in Accounting Principle [Line Items] |  |  |  |  |
Cumulative effect adjustment |  |  |  |  | (400)
Estimated Forfeitures [Member] | Other Noncurrent Assets [Member] |  |  |  |  |
New Accounting Pronouncements or Change in Accounting Principle [Line Items] |  |  |  |  |
Cumulative effect adjustment |  |  |  |  | (200)
Estimated Forfeitures [Member] | Additional Paid-in Capital [Member] |  |  |  |  |
New Accounting Pronouncements or Change in Accounting Principle [Line Items] |  |  |  |  |
Cumulative effect adjustment |  |  |  |  | 600
Excess Tax Benefits [Member] | (Deficit) [Member] |  |  |  |  |
New Accounting Pronouncements or Change in Accounting Principle [Line Items] |  |  |  |  |
Cumulative effect adjustment |  |  |  |  | $ 9,000
Minimum [Member] |  |  |  |  |
New Accounting Pronouncements or Change in Accounting Principle [Line Items] |  |  |  |  |
Operating lease liabilities |  |  | $ 100,000 |  |
Operating lease ROU assets |  |  | 91,000 |  |
Maximum [Member] |  |  |  |  |
New Accounting Pronouncements or Change in Accounting Principle [Line Items] |  |  |  |  |
Operating lease liabilities |  |  | 105,000 |  |
Operating lease ROU assets |  |  | $ 96,000 |  |

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- Definition Amount of short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Excludes cash and cash equivalents within disposal group and discontinued operation. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.1) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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- Definition The rate applied as of the balance sheet date to reduce the undiscounted amount of a guarantee fund and other insurance-related assessments to present value. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 405 -SubTopic 30 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6392405&loc=d3e24119-109301 + Details
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- Definition The present value of the liability as of the balance sheet date representing required funding mandated by statute or regulatory authority that is related directly or indirectly to underwriting activities, including pools for self-insurance and excluding premium taxes and income taxes. The funds derived from the assessments generally enable a government guarantor to pay insurance claims in the event that the underwriting insurer is insolvent or otherwise unable to meet its payment obligations. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 405 -SubTopic 30 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6392405&loc=d3e24119-109301 + Details
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