Long-term Debt Schedule of Debt Maturities (Details) ¥ in Millions, $ in Millions						9 Months Ended
	Oct. 25, 2015 USD ($)	Jul. 28, 2015 USD ($)	Jul. 08, 2015 USD ($)	Jul. 01, 2015 USD ($)	Apr. 01, 2015 USD ($)	Oct. 31, 2015 USD ($)	Oct. 31, 2014 USD ($)	Jul. 28, 2015 JPY (¥)
Debt Instrument [Line Items]
Repayments of Long-term Debt						$ 4,422	$ 3,883
Unsecured debt
Debt Instrument [Line Items]
Repayments of Long-term Debt						$ 4,230
Unsecured debt | 2.875% Fixed Rate Debt, Due 2015 [Member]
Debt Instrument [Line Items]
Principal Amount					$ 750
Interest Rate					2.875%
Repayments of Long-term Debt					$ 750
Unsecured debt | 4.500% Fixed Rate Debt, Due 2015 [Member]
Debt Instrument [Line Items]
Principal Amount				$ 750
Interest Rate				4.50%
Repayments of Long-term Debt				$ 750
Unsecured debt | 2.250% Fixed Rate Debt, Due 2015 [Member]
Debt Instrument [Line Items]
Principal Amount			$ 750
Interest Rate			2.25%
Repayments of Long-term Debt			$ 750
Unsecured debt | Variable Rate Debt, Due 2015 [Member]
Debt Instrument [Line Items]
Principal Amount | ¥								¥ 30,000
Repayments of Long-term Debt		$ 243
Unsecured debt | .940% Fixed Rate Debt, Due 2015 [Member]
Debt Instrument [Line Items]
Principal Amount | ¥								¥ 60,000
Interest Rate								0.94%
Repayments of Long-term Debt		$ 487
Unsecured debt | 1.500% Fixed Rate Debt, Due 2015 [Member]
Debt Instrument [Line Items]
Principal Amount	$ 1,250
Interest Rate	1.50%
Repayments of Long-term Debt	$ 1,250