Debt (Schedule of Long-Term Debt) (Details) (USD $) In Millions, unless otherwise specified	Apr. 30, 2013	Feb. 25, 2013	Apr. 30, 2012
Long - term debt
Total long term debt	$ 999		$ 506
Less current portion	2		3
Total Long term debt excluding current portion	997		503
5.0% notes due in fiscal 2014 [Member]
Long - term debt
Total long term debt	0		251
Interest rate on long term debt (percent)	5.00%	5.00%	5.00%
2.5% notes, due in fiscal 2016 [Member]
Long - term debt
Total long term debt	249		249
Interest rate on long term debt (percent)	2.50%		2.50%
1.0% notes due in fiscal 2018 [Member]
Long - term debt
Total long term debt	249		0
Interest rate on long term debt (percent)	1.00%		1.00%
2.25% notes due in Fiscal 2023 [Member]
Long - term debt
Total long term debt	249		0
Interest rate on long term debt (percent)	2.25%		2.25%
3.75% notes due in Fiscal 2043 [Member]
Long - term debt
Total long term debt	250		0
Interest rate on long term debt (percent)	3.75%		3.75%
Other long-term debt [Member]
Long - term debt
Total long term debt	$ 2		$ 6