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Stockholders' Equity (Valuation Assumptions) (Details)	12 Months Ended
Stockholders' Equity (Valuation Assumptions) (Details)	Apr. 27, 2012	Apr. 29, 2011	Apr. 30, 2010
Stock Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected term in years	4 years 9 months 18 days	4 years 9 months 18 days	4 years 6 months
Risk-free interest rate	1.50%	2.01%	2.27%
Volatility	36.00%	37.00%	41.00%
Employee Stock Purchase Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected term in years	1 year 2 months 12 days	1 year 2 months 12 days	1 year 3 months 18 days
Risk-free interest rate	0.19%	0.37%	0.39%
Volatility	44.00%	39.00%	39.00%

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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