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Stock-Based Awards - Tax Benefit Recognized (Details) - USD ($) $ in Thousands | 6 Months Ended | 12 Months Ended
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Jan. 27, 2018 | Jul. 29, 2017 | Jul. 30, 2016 | Jul. 25, 2015
Disclosure of Compensation Related Costs, Share-based Payments [Abstract] |  |  |  |
Stock-based compensation | $ 13,277 | $ 20,805 | $ 16,850 | $ 13,923
Income tax effect of stock-based compensation | 4,793 | $ 7,996 | $ 6,436 | $ 5,458
Cash tax benefit realized from option exercises and stock vestings | $ 7,800 |  |  |

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- Definition Effective Income Tax Rate Reconciliation, Share-based Compensation, Excess Tax Benefit, Amount + References No definition available. + Details
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- Definition The total recognized tax benefit related to compensation cost for equity-based payment arrangements recognized in income during the period. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (h)(1)(i) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
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- Definition The aggregate amount of noncash, equity-based employee remuneration. This may include the value of stock or unit options, amortization of restricted stock or units, and adjustment for officers' compensation. As noncash, this element is an add back when calculating net cash generated by operating activities using the indirect method. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=66902209&loc=d3e3602-108585 + Details
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