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Employee Benefit Plans - Narratives (Details) - USD ($) $ in Millions | 12 Months Ended
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Jul. 29, 2017 | Jul. 30, 2016 | Jul. 25, 2015
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |  |
Defined contribution maximum annual contribution for employee | 75.00% |  |
Defined contribution employer match | 30.00% |  |
Defined contribution employer match | 5.00% |  |
Employer contribution amount | $ 5.0 | $ 4.8 | $ 4.0
Multiemployer plan periodic withdraw liability | $ 0.1 |  |
Maximum |  |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |  |
Plan contribution | 5.00% |  |
Multiemployer plans, red zone threshold | 65.00% |  |
Multiemployer plans, yellow zone threshold | 80.00% |  |
Minimum |  |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |  |
Multiemployer plans, yellow zone threshold | 65.00% |  |
Multiemployer plans, green zone threshold | 80.00% |  |

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- Definition The company contribution to a multiemployer plan as a percentage of total contributions. + References No definition available. + Details
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- Definition Multiemployer Plan Periodic Withdraw Liability + References No definition available. + Details
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- Definition Multiemployer Plans, Green Zone Threshold + References No definition available. + Details
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- Definition Multiemployer Plans, Red Zone Threshold + References No definition available. + Details
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- Definition Multiemployer Plans, Yellow Zone Threshold + References No definition available. + Details
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
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- Definition Amount of discretionary contributions made by an employer to a defined contribution plan. + References No definition available. + Details
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Data Type: | xbrli:monetaryItemType
Balance Type: | debit
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- Definition Percentage of employees' gross pay for which the employer contributes a matching contribution to a defined contribution plan. + References No definition available. + Details
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- Definition Percentage employer matches of the employee's percentage contribution matched. + References No definition available. + Details
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- Definition Maximum percentage of employee gross pay the employee may contribute to a defined contribution plan. + References No definition available. + Details
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