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Stock-Based Awards - Narratives (Details) - USD ($) $ / shares in Units, $ in Thousands | 6 Months Ended | 12 Months Ended
--- | --- | ---
Jan. 27, 2018 | Jan. 28, 2017 | Jul. 29, 2017 | Jul. 30, 2016 | Jul. 25, 2015
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |
Cash tax benefit realized from option exercises and stock vestings | $ 7,800 |  |  |  |
Proceeds from stock options exercised | $ 745 |  | $ 1,449 | $ 2,745 | $ 8,922
Stock Options |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |
Share Price | $ 119.30 |  |  |  |
Share based compensation intrinsic value | $ 4,500 |  | 7,800 | 15,000 | 24,900
Unrecognized compensation expense related to stock options | $ 2,800 |  |  |  |
Total compensation cost not yet recognized, period for recognition | 2 years 6 months 1 day |  |  |  |
Proceeds from stock options exercised | $ 700 |  | $ 1,400 | 2,700 | 8,900
RSUs |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |
Unrecognized compensation expense related to stock options | $ 8,600 |  |  |  |
Total compensation cost not yet recognized, period for recognition | 2 years 6 months 1 day |  |  |  |
Granted (in shares) | 29,672 |  |  |  |
Forfeited or canceled (in shares) | 2,357 |  |  |  |
Shares outstanding (in shares) | 133,896 |  | 187,465 |  |
Share units vested (in shares) | 80,884 |  |  |  |
Share based compensation vested in period |  | $ 37,700 | $ 33,200 | $ 39,100 | $ 15,200
Performance RSUs |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |
Unrecognized compensation expense related to stock options | $ 18,300 |  |  |  |
Total compensation cost not yet recognized, period for recognition | 1 year 11 months 1 day |  |  |  |
Compensation expense | $ 7,900 |  |  |  |
RSUs outstanding (in shares) |  | 99,627 |  |  |
Granted (in shares) | 138,261 |  |  |  |
Forfeited or canceled (in shares) | 29,350 |  |  |  |
Shares outstanding (in shares) | 390,327 |  | 553,882 |  |
Share units vested (in shares) | 272,466 |  |  |  |
Target Share Units |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |
Shares outstanding (in shares) |  | 278,963 |  |  |
Supplemental Shares |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |
Granted (in shares) |  | 38,634 |  |  |
Forfeited or canceled (in shares) |  | 21,139 |  |  |
Shares outstanding (in shares) |  | 111,364 |  |  |

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- Definition Share-based compensation by share-based payment award, equity awards other than options, target amount of performance shares + References No definition available. + Details
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- Definition Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. + 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 (i) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
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- Definition Unrecognized cost of unvested options awarded to employees as compensation. + References No definition available. + Details
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- Definition The cash inflow associated with the amount received from holders exercising their stock options. This item inherently excludes any excess tax benefit, which the entity may have realized and reported separately. + 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 (j) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 14 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=66902209&loc=d3e3255-108585 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Financing Activities -URI http://asc.fasb.org/extlink&oid=6513228 + Details
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- Definition The number of equity-based payment instruments, excluding stock (or unit) options, that were forfeited during the reporting 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 (c)(1)(iv)(3) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
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- Definition The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan). + 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 (c)(2)(iii)(1) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
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- Definition The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date. + 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 (c)(2)(i)-(ii) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
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- Definition The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting 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 (c)(2)(iii)(2) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
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- Definition Fair value of share-based awards for which the grantee gained the right by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash. + 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 (d)(2) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
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- Definition Amount of accumulated difference between fair value of underlying shares on dates of exercise and exercise price on options exercised (or share units converted) into shares. + 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 (d)(2) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
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