Stock Based Compensation (Details 3) (USD $) In Thousands, except Share data, unless otherwise specified	12 Months Ended
Apr. 26, 2015	Apr. 27, 2014	Apr. 28, 2013
Additional information on equity compensation plan
Shares available for future issuance	1,779,225
Deferred tax benefits associated with stock exercises and restricted stock vesting	$ 5,421
Reduction of tax benefit from vested and exercised stock based compensation	0		(10)
Stock Repurchase
Number of shares of common stock authorized for repurchase by the entity	6,000,000
Number of shares of common stock repurchased since plan inception	4,895,792
Number of shares of common stock retired since plan inception	553,800
Number of shares of common stock repurchased	0	0	0
Restricted Stock
Restricted Stock:
Fair value of restricted stock vested during the year	3,238	3,660	5,272
Restricted Stock \| Second tranche
Additional information on equity compensation plan
Shares available for future issuance	465,679
Stock Options
Stock Options:
Intrinsic value of stock options exercised	57		41
Proceeds from stock options exercises	$ 74		$ 668

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Number of shares of common stock that have been repurchased from the date of the inception of the plan until the balance sheet date.

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Number of shares of common stock that have been retired from the date of the inception of the plan until the balance sheet date.

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Amount of increase in additional paid in capital (APIC) resulting from a tax benefit associated with share-based compensation plan other than an employee stock ownership plan (ESOP). Includes, but is not limited to, excess tax benefit.

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-Publisher FASB

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from share-based compensation.

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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.

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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.

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The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

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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.

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Number of shares that have been repurchased during the period and have not been retired and are not held in treasury. Some state laws may govern the circumstances under which an entity may acquire its own stock and prescribe the accounting treatment therefore. This element is used when state law does not recognize treasury stock.

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-Publisher SEC

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The number of shares authorized to be repurchased by an entity's Board of Directors under a stock repurchase plan.

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