Represents the period from grant date after which awards begin to vest.

No definition available.

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- Definition

The number of restricted stock units that were awarded in accordance with market performance conditions during the period.

+ References

No definition available.

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- Definition

The adjusted forfeiture rate that is used in valuing a share-based compensation award on its own shares.

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No definition available.

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The forfeiture rate assumption that is used in valuing a share-based compensation award on its own shares.

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- Definition

Description of award terms as to how many shares or portion of an award are no longer contingent commencing one year after the date of grant, on satisfaction of either a service condition, market condition or a performance condition, thereby giving the employee the legal right to convert the award to shares, shown as a percentage.

+ References

No definition available.

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Description of award terms as to how many shares or portion of an award are no longer contingent on anniversary of grant date, on satisfaction of either a service condition, market condition or a performance condition, thereby giving the employee the legal right to convert the award to shares, shown as a percentage.

+ References

No definition available.

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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

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- Definition

Unrecognized cost of unvested share-based awards, other than options, awarded to employees as compensation.

+ References

No definition available.

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- Definition

Unrecognized cost of unvested options awarded to employees as compensation.

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No definition available.

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- Definition

Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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-Name Accounting Standards Codification
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-SubTopic 10
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-Paragraph 2
-Subparagraph (a)(1)
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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
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-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(2)(iii)(1)
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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

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
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-Paragraph 2
-Subparagraph (c)(2)(iii)(1)
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- References

No definition available.

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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

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)(iii)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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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.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (f)(2)(ii)
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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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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.

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- Definition

Gross number of share options (or share units) granted during the period.

+ References

No definition available.

+ 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.

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-Publisher FASB
-Name Accounting Standards Codification
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- Definition

Number of share instruments newly issued under a share-based compensation plan.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
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- Definition

Percentage of vesting of share-based compensation awards.

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-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
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-Paragraph 2
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- Definition

Period from grant date that an equity-based award expires, 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
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-Section 50
-Paragraph 2
-Subparagraph (a)(2)
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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
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-Name Accounting Standards Codification
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-SubTopic 10
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-Publisher SEC
-Name Staff Accounting Bulletin (SAB)
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Stock Based Compensation (Details) - USD ($) $ / shares in Units, $ in Thousands		3 Months Ended	9 Months Ended	12 Months Ended
	Apr. 26, 2016	Jan. 24, 2016	Jan. 24, 2016	Apr. 26, 2015
Stock options pricing model assumptions
Weighted average expected volatility			42.61%
Expected dividend yield			0.00%
Weighted average expected term (in years)			5 years
Weighted average risk-free interest rate			1.36%
Restricted stock units ("RSUs")
Stock based compensation
Number of restricted stock units awarded in accordance with market performance conditions during the period				1,532,417
Restricted stock units ("RSUs") \| Vesting on April 26, 2015
Stock based compensation
Vesting rights (as a percent)				50.00%
Restricted stock units ("RSUs") \| Second tranche
Stock based compensation
Unrecognized compensation cost		$ 145	$ 145
Restricted stock units ("RSUs") \| Second tranche \| Forecast
Stock based compensation
Shares issued during the period	465,679
Restricted stock units ("RSUs") \| Employee
Stock based compensation
Granted (in shares)			104,982
Weighted average grant-date fair value (in dollars per share)			$ 14.89
Vesting period (in years)			3 years
Period from grant date after which awards begin to vest			1 year
Adjusted forfeiture rate (as a percent)		25.00%
Unrecognized compensation cost		$ 579	$ 579
Performance Stock Units \| Employee
Stock based compensation
Granted (in shares)			157,772
Period from grant date after which awards begin to vest			3 years
Adjusted forfeiture rate (as a percent)		37.00%
Unrecognized compensation cost		$ 1,175	$ 1,175
Restricted Stock
Stock based compensation
Unrecognized compensation cost		$ 1,524	$ 1,524
Remaining weighted average vesting period of unrecognized compensation cost			1 year 22 days
Restricted Stock \| Vesting on each anniversary of the grant
Stock based compensation
Vesting rights on each anniversary of grant date (as a percent)			33.00%
Restricted Stock \| Employee
Stock based compensation
Granted (in shares)			102,922
Weighted average grant-date fair value (in dollars per share)			$ 20.10
Estimated forfeiture rate (as a percent)			10.00%
Restricted Stock \| Director
Stock based compensation
Granted (in shares)			38,431
Weighted average grant-date fair value (in dollars per share)			$ 18.21
Estimated forfeiture rate (as a percent)			0.00%
Stock Options
Stock based compensation
Period from grant date after which awards begin to vest			1 year
Adjusted forfeiture rate (as a percent)		30.00%
Granted (in shares)			378,905
Maximum term of options			7 years
Percentage of the shares vest commencing one year after the date of grant			20.00%
Granted (in dollars per share)			$ 5.764
Unrecognized compensation cost for unvested stock options		$ 940	$ 940