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Employee Benefit Plans - Narratives (Details) - USD ($) $ in Millions | 1 Months Ended | 6 Months Ended | 12 Months Ended |
--- | --- | --- | --- | ---
Oct. 31, 2016 | Jan. 27, 2018 | Jul. 29, 2017 | Jul. 30, 2016 | Jul. 25, 2015 | Nov. 30, 2016
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 |  | $ 1.7 | $ 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% |  |  |  |
The Plan (EIN 13-6123601) |  |  |  |  |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |  |  |  |  |
Claim amount | $ 13.0 |  |  |  |  |

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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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