Special Charges and Certain Litigation Charges, Net Special Charges (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended		6 Months Ended
	Oct. 25, 2013	Oct. 26, 2012	Oct. 25, 2013	Oct. 26, 2012
Special Charges [Abstract]
Special Charges	$ 0	$ 0	$ 40	$ 0