Stockholders' Equity (Income Tax Benefits (Charges) Associated with Employee Stock Transactions) (Details) (USD $) In Millions	12 Months Ended
Apr. 29, 2011	Apr. 30, 2010	Apr. 24, 2009
Stockholders' Equity
Income tax benefits (charges) associated with employee stock transactions	$ 128.5	$ (0.9)	$ 45.4

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