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Basis of Presentation and Accounting Policies - Revenue Recognition (Details) - USD ($) $ in Thousands | 6 Months Ended | 12 Months Ended
--- | --- | ---
Jan. 27, 2018 | Jul. 29, 2017 | Jul. 30, 2016 | Jul. 25, 2015
Accounting Policies [Abstract] |  |  |  |
Insurance recoveries for accrued insurance claims | $ 6,722 | $ 9,243 | $ 5,714 |
Maximum | Revenue Recognized Using Cost To Cost Percentage of Completion Method |  |  |  |
Revenue from External Customer [Line Items] |  |  |  |
Percentage of Revenue | 5.00% | 5.00% | 5.00% | 5.00%

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- Definition Carrying amount due after one year of the balance sheet date (or one operating cycle, if longer) of amount due in settlement of a claim for reimbursement from an insurance company when the Company has suffered a loss covered under an insurance policy. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.17) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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