Subsequent Event - Additional Information (Detail) (USD $) In Millions, unless otherwise specified	12 Months Ended			0 Months Ended
	Apr. 25, 2014	Apr. 26, 2013	Apr. 27, 2012	Jun. 05, 2014 Subsequent Event Senior Notes Due 2021
Subsequent Event [Line Items]
Notes issued, principal amount	$ 1,000.0	$ 2,264.9		$ 500.0
Notes issued, interest rate				3.375%
Notes issued, maturity date				Jun. 15, 2021
Proceeds from notes issued	$ 0	$ 987.3	$ 0	$ 494.7
Note repurchase price, percentage of principal amount of notes				101.00%