Derivatives and Foreign Exchange Risk Management (Effect on Balance Sheet) (Details) (USD $) In Millions, unless otherwise specified	Jan. 27, 2012	Apr. 29, 2011
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset	$ 293	$ 130
Derivative Liability, Fair Value, Gross Liability	114	303
Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset	291	129
Derivative Liability, Fair Value, Gross Liability	113	299
Designated as Hedging Instrument | Foreign Exchange Contract | Prepaid Expenses and Other Current Assets
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset	104	19
Designated as Hedging Instrument | Foreign Exchange Contract | Other Assets
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset	23	1
Designated as Hedging Instrument | Foreign Exchange Contract | Other Accrued Expenses
Derivatives, Fair Value [Line Items]
Derivative Liability, Fair Value, Gross Liability	58	235
Designated as Hedging Instrument | Foreign Exchange Contract | Other Long-term Liabilities
Derivatives, Fair Value [Line Items]
Derivative Liability, Fair Value, Gross Liability	12	64
Designated as Hedging Instrument | Interest Rate Contract | Other Assets
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset	164	109
Designated as Hedging Instrument | Interest Rate Contract | Other Long-term Liabilities
Derivatives, Fair Value [Line Items]
Derivative Liability, Fair Value, Gross Liability	43
Not Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset	2	1
Derivative Liability, Fair Value, Gross Liability	1	4
Not Designated as Hedging Instrument | Foreign Exchange Contract | Prepaid Expenses and Other Current Assets
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset	2	1
Not Designated as Hedging Instrument | Foreign Exchange Contract | Other Accrued Expenses
Derivatives, Fair Value [Line Items]
Derivative Liability, Fair Value, Gross Liability	$ 1	$ 4