Employee Retirement Savings Plan and Deferred Compensation Plan (Details) (USD $)	12 Months Ended
Apr. 26, 2013	Apr. 27, 2012	Apr. 29, 2011
Employee Retirement and Deferred Compensation Plan [Abstract]
Defined contribution plan, percent employee contributions matched (in Percent)	50.00%
Defined contribution plan, maximum matched eligible earning (in Percent)	6.00%
Defined contribution plan, vesting period (in Duration)	5 years
Defined contribution plan, expenses incurred	$ 1.4	$ 1.3	$ 1.1
Deferred compensation plan, percent of base salary compensation eligible for deferral (in Percent)	50.00%
Deferred compensation plan, recorded liability	$ 100,000
Deferred compensation plan percent of bonus or performance-based compensation eligible for deferral (in Percent)	100.00%

Deferred compensation plan, percent of base salary compensation eligible for deferral, in percent.

No definition available.

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- Definition

Deferred compensation plan percent of bonus or performance-based compensation eligible for deferral, in percent.

+ References

No definition available.

+ Details

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- Definition

Defined contribution plan, percent employee contributions matched.

+ References

No definition available.

+ Details

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- Definition

Vesting-period contributions are subject to under the Employee Retirement Savings Plan, a defined contribution plan.

+ References

No definition available.

+ Details

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- Definition

Aggregate carrying value as of the balance sheet date of the liabilities for all deferred compensation arrangements payable beyond one year (or the operating cycle, if longer).

+ References

No definition available.

+ Details

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- Details

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- Definition

The amount of the cost recognized during the period for defined contribution plans.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 70

-Section 50

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6414718&loc=d3e28014-114942

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 132R

-Paragraph 11

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

+ Details

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Period Type:	duration

- 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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