Derivatives and Foreign Exchange Risk Management , Offsetting of Assets and Liabilities (Details) - USD ($) $ in Millions	Apr. 24, 2015	Apr. 25, 2014
Offsetting Assets [Line Items]
Derivative assets, gross amount	$ 733	$ 175
Gross amount not offset on the Balance Sheet, financial instruments	(71)	(95)
Gross amount not offset on the Balance Sheet, cash collateral (received) or pledged	(338)	0
Derivative assets, net amount	324	80
Derivative liability, gross amount	(116)	(127)
Gross amount not offset on the Balance Sheet, financial instrument	71	95
Gross amount not offset on the Balance Sheet, cash collateral (received) or pledged	8	0
Derivative liabilities, net amount	(37)	(32)
Total derivatives, gross amount of recognized assets/(liabilities)	617	48
Total derivatives, gross amount not offset on the Balance Sheet, financial instruments	0	0
Total derivatives, gross amount not offset on the Balance Sheet, cash collateral (received) or pledged	(330)	0
Total derivatives, net amount	287	48
Foreign Currency Exchange Rate Contracts
Offsetting Assets [Line Items]
Derivative assets, gross amount	644	89
Gross amount not offset on the Balance Sheet, financial instruments	(61)	(64)
Gross amount not offset on the Balance Sheet, cash collateral (received) or pledged	(325)	0
Derivative assets, net amount	258	25
Derivative liability, gross amount	(45)	(116)
Gross amount not offset on the Balance Sheet, financial instrument	31	84
Gross amount not offset on the Balance Sheet, cash collateral (received) or pledged	0	0
Derivative liabilities, net amount	(14)	(32)
Interest Rate Contracts
Offsetting Assets [Line Items]
Derivative assets, gross amount	89	86
Gross amount not offset on the Balance Sheet, financial instruments	(10)	(31)
Gross amount not offset on the Balance Sheet, cash collateral (received) or pledged	(13)	0
Derivative assets, net amount	66	55
Derivative liability, gross amount	(71)	(11)
Gross amount not offset on the Balance Sheet, financial instrument	40	11
Gross amount not offset on the Balance Sheet, cash collateral (received) or pledged	8	0
Derivative liabilities, net amount	$ (23)	$ 0