Derivatives and Foreign Exchange Risk Management, Fair Value Hedges (Details) (USD $) In Millions, unless otherwise specified								3 Months Ended		6 Months Ended		3 Months Ended	6 Months Ended				3 Months Ended		6 Months Ended
	Oct. 24, 2014 Interest Rate Swap	Apr. 25, 2014 Interest Rate Swap	Oct. 24, 2014 Senior Notes 2010 Due 2015	Oct. 24, 2014 Senior Notes 2005 Due 2016	Oct. 24, 2014 Senior Notes 2011 Due 2016	Oct. 24, 2014 Senior Notes 2011 Due 2021	Oct. 24, 2014 Senior Notes 2012 Due 2022	Oct. 24, 2014 Cash Flow Hedging [Member]	Oct. 25, 2013 Cash Flow Hedging [Member]	Oct. 24, 2014 Cash Flow Hedging [Member]	Oct. 25, 2013 Cash Flow Hedging [Member]	Oct. 24, 2014 Fair Value Hedging [Member] Interest Rate Swap	Oct. 24, 2014 Fair Value Hedging [Member] Interest Rate Swap	Oct. 24, 2014 Designated as Hedging Instrument [Member] Cash Flow Hedging [Member] Interest Rate Swap	Oct. 24, 2014 Designated as Hedging Instrument [Member] Fair Value Hedging [Member] Interest Rate Swap	Apr. 25, 2014 Designated as Hedging Instrument [Member] Fair Value Hedging [Member] Interest Rate Swap	Oct. 24, 2014 Interest Expense Cash Flow Hedging [Member] Interest Rate Swap	Oct. 25, 2013 Interest Expense Cash Flow Hedging [Member] Interest Rate Swap	Oct. 24, 2014 Interest Expense Cash Flow Hedging [Member] Interest Rate Swap	Oct. 25, 2013 Interest Expense Cash Flow Hedging [Member] Interest Rate Swap
Derivative [Line Items]
Derivative Instruments, Gain (Loss) Reclassified from Accumulated OCI into Income, Effective Portion, Net								$ 21	$ 9	$ 19	$ 26						$ 2	$ 2	$ 4	$ 4
Fair Value Hedges
Derivative, Notional Amount														1,675	2,625	2,625
Interest rate derivatives hedged items													the Company’s $1.250 billion 3.000 percent 2010 Senior Notes and the $600 million 4.750 percent 2005 Senior Notes classified as short-term borrowings, the $500 million 2.625 percent 2011 Senior Notes, the $500 million 4.125 percent 2011 Senior Notes, and the $675 million 3.125 percent 2012 Senior Notes
Principal amount			1,250	600	500	500	675
Stated interest rate			3.00%	4.75%	2.625%	4.125%	3.125%
Unrealized gain on interest rate fair value hedging instruments												81
Unrealized loss on interest rate fair value hedged items												81
Unrealized Gain (Loss) on Cash Flow Hedging Instruments	$ (21)	$ 7