Debt (Details) (USD $)	3 Months Ended	12 Months Ended
	Jul. 27, 2011	Apr. 27, 2011
Debt Instrument [Line Items]
Total credit agreements supporting commercial paper borrowings	$ 1,500,000,000	$ 1,200,000,000
Maturity date	June 2016	April 2012
3.48% Private Placement Notes [Member]
Debt Instrument [Line Items]
Private placement notes, face amount	500,000,000
Private placement notes, average interest rate	3.48%
3.38% Private Placement Notes [Member]
Debt Instrument [Line Items]
Private placement notes, face amount	100,000,000
Private placement notes, average interest rate	3.38%
6.625% U.S. Dollar Notes due July 2011 [Member]
Debt Instrument [Line Items]
Private placement notes, face amount	$ 750,000,000
Private placement notes, average interest rate	6.625%