Condensed Consolidated Statements of Comprehensive Income (Parenthetical) (USD $) In Millions, unless otherwise specified	3 Months Ended		6 Months Ended
	Oct. 24, 2014	Oct. 25, 2013	Oct. 24, 2014	Oct. 25, 2013
Other Comprehensive Income (Loss), Tax
Unrealized gain/(loss) on investments, tax expense/(benefit)	$ (19)	$ 17	$ 13	$ (37)
Net change in retirement obligations, tax expense/(benefit)	6	8	12	17
Unrealized gain/(loss) on derivatives, tax expense/(benefit)	$ 68	$ (53)	$ 89	$ (52)