Derivatives and Foreign Exchange Risk Management, Freestanding Derivative Forward Contracts and Cash Flow Hedges (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended	6 Months Ended					3 Months Ended		3 Months Ended		6 Months Ended		3 Months Ended		6 Months Ended		3 Months Ended		6 Months Ended		3 Months Ended		6 Months Ended		3 Months Ended		6 Months Ended		3 Months Ended		6 Months Ended								3 Months Ended
	Oct. 24, 2014	Oct. 24, 2014	Oct. 25, 2013	Apr. 25, 2014	Oct. 24, 2014 Foreign Currency Exchange Rate Contracts	Apr. 25, 2014 Foreign Currency Exchange Rate Contracts	Oct. 24, 2014 Interest Rate Swap	Apr. 25, 2014 Interest Rate Swap	Oct. 24, 2014 Other Expense, Net Foreign Currency Exchange Rate Contracts	Oct. 25, 2013 Other Expense, Net Foreign Currency Exchange Rate Contracts	Oct. 24, 2014 Other Expense, Net Foreign Currency Exchange Rate Contracts	Oct. 25, 2013 Other Expense, Net Foreign Currency Exchange Rate Contracts	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 Cash Flow Hedging [Member] Foreign Currency Exchange Rate Contracts	Oct. 25, 2013 Cash Flow Hedging [Member] Foreign Currency Exchange Rate Contracts	Oct. 24, 2014 Cash Flow Hedging [Member] Foreign Currency Exchange Rate Contracts	Oct. 25, 2013 Cash Flow Hedging [Member] Foreign Currency Exchange Rate Contracts	Oct. 24, 2014 Cash Flow Hedging [Member] Other Expense, Net Foreign Currency Exchange Rate Contracts	Oct. 25, 2013 Cash Flow Hedging [Member] Other Expense, Net Foreign Currency Exchange Rate Contracts	Oct. 24, 2014 Cash Flow Hedging [Member] Other Expense, Net Foreign Currency Exchange Rate Contracts	Oct. 25, 2013 Cash Flow Hedging [Member] Other Expense, Net Foreign Currency Exchange Rate Contracts	Oct. 24, 2014 Cash Flow Hedging [Member] Interest Expense Interest Rate Swap	Oct. 25, 2013 Cash Flow Hedging [Member] Interest Expense Interest Rate Swap	Oct. 24, 2014 Cash Flow Hedging [Member] Interest Expense Interest Rate Swap	Oct. 25, 2013 Cash Flow Hedging [Member] Interest Expense Interest Rate Swap	Oct. 24, 2014 Cash Flow Hedging [Member] Cost of Products Sold Foreign Currency Exchange Rate Contracts	Oct. 25, 2013 Cash Flow Hedging [Member] Cost of Products Sold Foreign Currency Exchange Rate Contracts	Oct. 24, 2014 Cash Flow Hedging [Member] Cost of Products Sold Foreign Currency Exchange Rate Contracts	Oct. 25, 2013 Cash Flow Hedging [Member] Cost of Products Sold Foreign Currency Exchange Rate Contracts	Oct. 24, 2014 Not Designated as Hedging Instrument [Member] Foreign Currency Exchange Rate Contracts	Apr. 25, 2014 Not Designated as Hedging Instrument [Member] Foreign Currency Exchange Rate Contracts	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 Designated as Hedging Instrument [Member] Cash Flow Hedging [Member] Foreign Currency Exchange Rate Contracts	Apr. 25, 2014 Designated as Hedging Instrument [Member] Cash Flow Hedging [Member] Foreign Currency Exchange Rate Contracts	Oct. 24, 2014 Designated as Hedging Instrument [Member] Cash Flow Hedging [Member] Interest Rate Swap
Derivative Instruments, Gain (Loss) [Line Items]
Currency exchange rate gains/(losses)	$ 14	$ 2	$ 3
Freestanding Derivative Forward Contracts
Gain (loss) on foreign currency derivatives not designated as hedging instruments									73	(46)	49	(17)
Cash Flow Hedges
Maximum remaining maturity of foreign currency derivatives													3 years
Gains/(losses) recognized in OCI on effective portion of derivative													229	(130)	291	(154)	229	(130)	291	(154)
Derivative Instruments, Gain (Loss) Reclassified from Accumulated OCI into Income, Effective Portion, Net													21	9	19	26					20	23	21	55	2	2	4	4	1	(14)	(2)	(29)
Derivative, Notional Amount, Contracts Entered Into During Period																																							1,425
Weighted average fixed rate of interest rate derivatives, contracts entered into during the period							2.88%
Derivative, Notional Amount					6,790	8,051																											1,901	2,202	2,625	2,625	4,889	5,849	1,675
Weighted average fixed rate of interest rate derivatives							2.87%
Unrealized Gain (Loss) on Cash Flow Hedging Instruments							(21)	7
After-tax net unrealized (losses)/gains associated with cash flow hedging instruments recorded in AOCI	114	114		(44)
Cash flow hedge unrealized gains to be reclassified over the next 12 months	$ 79