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Accrued Insurance Claims - Narratives (Details) | 6 Months Ended | 12 Months Ended |
--- | --- | --- | ---
Jan. 27, 2018 USD ($) state | Jul. 29, 2017 USD ($) | Jul. 30, 2016 USD ($) | Jul. 25, 2015 USD ($)
Accrued Insurance Claims [Line Items] |  |  |  |
Number of states with state-sponsored insurance fund | state | 2 |  |  |
Aggregate stop loss coverage for automobile liability, general liability, and workers' compensation claims before adjustment | $ 67,100,000 | $ 103,700,000 | $ 84,600,000 |
Insurance liability, annual retained risk loss | 400,000 |  |  | $ 250,000
Losses Incurred but not Recognized from Insurance Claims | 53,300,000 | $ 50,000,000 | $ 45,000,000 |
Maximum |  |  |  |
Accrued Insurance Claims [Line Items] |  |  |  |
Retained risk of loss, general liability and workers' compensation, maximum automobile liability | $ 1,000,000 |  |  |

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- Definition Accrued Insurance Claims [Line Items] + References No definition available. + Details
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- Definition Aggregate Stop Loss Coverage for Automobile Liability, General Liability, and Workers' Compensation Claims Before Adjustment Increase + References No definition available. + Details
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- Definition The maximum retained risk of loss per occurrence for automobile liability. + References No definition available. + Details
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- Definition Annual retained risk of loss under the employee health plan. + References No definition available. + Details
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- Details
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