Potential Compensation Expense for Performance Based Shares If Performance Goals Are Met

No definition available.

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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.

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- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Cancelled in Period

+ References

No definition available.

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- Definition

Share-based Compensation by Share-based Payment Award, Equity Awards Other than Options, Shares Expected to Vest

+ References

No definition available.

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- Definition

Share-based Compensation by Share-based Payment Award, Equity Awards Other than Options, Shares Expected to be Canceled

+ References

No definition available.

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- Definition

Aggregate proceeds received by the entity during the annual period from exercises of stock or unit options and conversion of similar instruments granted under equity-based payment arrangements.

+ References

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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

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- Definition

Unrecognized cost of unvested options awarded to employees as compensation.

+ References

No definition available.

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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

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- Definition

Estimated period over which an employee is required to provide service in exchange for the equity-based payment award, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

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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

+ Details

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- Definition

The weighted average fair value at grant date for nonvested equity-based awards issued 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

+ 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

+ 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

+ Details

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- Definition

The estimated dividend rate (a percentage of the share price) to be paid (expected dividends) to holders of the underlying shares over the option's term.

+ References

+ Details

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- Definition

The estimated measure of the percentage by which a share price is expected to fluctuate during a period. Volatility also may be defined as a probability-weighted measure of the dispersion of returns about the mean. The volatility of a share price is the standard deviation of the continuously compounded rates of return on the share over a specified period. That is the same as the standard deviation of the differences in the natural logarithms of the stock prices plus dividends, if any, over the period.

+ References

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- Definition

The risk-free interest rate assumption that is used in valuing an option on its own shares.

+ References

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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 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

+ Details

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- Definition

The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

+ References

+ Details

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- Definition

Price of a single share of a number of saleable stocks of a company.

+ References

No definition available.

+ Details

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- Definition

Expected term of share-based compensation awards, 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 (f)(2)(i)
-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 718
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SAB Topic 14.D.2)
-URI http://asc.fasb.org/extlink&oid=27013229&loc=d3e301413-122809

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Stock-Based Awards (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended	12 Months Ended
	Jul. 30, 2016	Jul. 29, 2017	Jul. 30, 2016	Jul. 25, 2015	Jul. 26, 2014	Jul. 29, 2016
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share Price						$ 94.05
Stock-based compensation			$ 16,850	$ 13,923	$ 12,596
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period, Intrinsic Value			15,000	24,900	8,400
Employee Service Share-based Compensation, Cash Received from Exercise of Stock Options			2,700	$ 8,900	$ 14,600
Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation expense related to stock options	$ 2,900		$ 2,900
Total compensation cost not yet recognized, period for recognition	2 years 6 months 29 days
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value			$ 78.20	$ 19.48	$ 17.43
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Risk Free Interest Rate			2.00%	2.10%	2.70%
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Term			7 years 3 months 29 days	8 years 9 months 11 days	8 years 9 months 11 days
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Volatility Rate			55.00%	54.50%	55.10%
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Dividend Rate			0.00%	0.00%	0.00%
RSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted (in dollars per shares)			$ 72.41	$ 31.42	$ 27.54
Unrecognized compensation expense related to stock options	$ 8,000		$ 8,000
Total compensation cost not yet recognized, period for recognition	2 years 7 months 25 days
Granted (in shares)			92,429
Shares outstanding (in shares)	251,264		251,264	322,008
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period, Fair Value			$ 39,100	$ 15,200	$ 11,700
Performance RSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted (in dollars per shares)			$ 77.86	$ 31.03	$ 27.66
Award service period			3 years
Unrecognized compensation expense related to stock options	$ 15,400		$ 15,400
Total compensation cost not yet recognized, period for recognition	1 year 4 months 24 days
Compensation expense	$ 4,300		$ 4,300
RSUs outstanding (in shares)			170,304
Granted (in shares)			238,209
Shares outstanding (in shares)	625,971		625,971	945,540
Target Share Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation			$ 10,400	$ 8,500
Shares outstanding (in shares)	500,681		500,681
Supplemental Shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation			$ 600
Granted (in shares)			67,905
Forfeited or cancelled (in shares)			169,790
Shares outstanding (in shares)	125,290		125,290
Scenario, Forecast \| Supplemental Shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation by Share-based Payment Award, Equity Awards Other than Options, Shares Expected to Vest		11,043
Share-based Compensation by Share-based Payment Award, Equity Awards Other than Options, Shares Expected to be Canceled		49,797