Goodwill And Purchased Intangible Assets (Purchased Intangible Assets With Finite Lives) (Details) (USD $) In Millions, unless otherwise specified									12 Months Ended			6 Months Ended
	Jan. 28, 2012	Jul. 30, 2011	Jan. 28, 2012 Technology [Member]	Jul. 30, 2011 Technology [Member]	Jan. 28, 2012 Customer Relationships [Member]	Jul. 30, 2011 Customer Relationships [Member]	Jan. 28, 2012 Other Purchased Intangible Assets [Member]	Jul. 30, 2011 Other Purchased Intangible Assets [Member]	Jul. 30, 2011 In-Process Research & Development, With Indefinite Lives [Member]	Jan. 28, 2012 Total Purchased Intangible Assets With Finite Lives [Member]	Jul. 30, 2011 Total Purchased Intangible Assets With Finite Lives [Member]	Jan. 28, 2012 In-Process Research & Development, With Indefinite Lives [Member]
Acquired Intangible Asset Balances by Major Asset Class [Line Items]
Total purchased intangible assets with finite lives, Gross			$ 2,187	$ 1,961	$ 2,263	$ 2,277	$ 122	$ 123		$ 4,572	$ 4,361
Total purchased intangible assets with finite lives, Gross			84
Total purchased intangible assets with finite lives, Accumulated Amortization	(2,345)	(1,998)	(737)	(561)	(1,505)	(1,346)	(103)	(91)		(2,345)	(1,998)
Total purchased intangible assets with finite lives, Net			1,450	1,400	758	931	19	32		2,227	2,363
In-process research & development, with indefinite lives, Gross									178			9
In-process research & development, with indefinite lives, net									178			9
Total, Gross	4,581	4,539
Total, Net	$ 2,236	$ 2,541