Stockholders' Equity - Schedule of Stock Options (Details) (USD $) In Millions, except Share data, unless otherwise specified	12 Months Ended
May 03, 2015	Apr. 27, 2014	Apr. 28, 2013
Number of Shares (in shares):
Options outstanding, beginning	2,621,844
Options exercised	(299,517)
Options canceled	(39,165)
Options outstanding, ending	2,283,162	2,621,844
Weighted-Average Exercise Price (in dollars per share):
Options outstanding, beginning, weighted average exercise price	$ 14.28
Options exercised, weighted average exercise price	$ 10.27
Options canceled, weighted average exercise price	$ 23.61
Options outstanding, ending weighted average exercise price	$ 14.64	$ 14.28
Options exercised, aggregate intrinsic value	$ 3.4	$ 14.2	$ 4.4
Options outstanding, intrinsic value	$ 19.5
Options outstanding ending, weighted average remaining contractual term	2 years 8 months 12 days

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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For presentations that combine terminations, the number of shares under options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the stock option plan or that expired.

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Weighted average price of options that were either forfeited or expired.

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Amount by which the current fair value of the underlying stock exceeds the exercise price of options outstanding.

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Number of options outstanding, including both vested and non-vested options.

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Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

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Weighted average remaining contractual term for option awards outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Weighted average price at which option holders acquired shares when converting their stock options into shares.

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Number of share options (or share units) exercised during the current period.

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