Goodwill and Purchased Intangible Assets (Details 2) (USD $)	12 Months Ended								12 Months Ended		12 Months Ended				12 Months Ended
	Oct. 31, 2011	Oct. 31, 2010	Oct. 31, 2011 IPR&D	Oct. 31, 2010 IPR&D	Oct. 31, 2011 Compaq trade name	Aug. 31, 2011 Compaq trade name	Aug. 02, 2011 Compaq trade name	Oct. 31, 2010 Compaq trade name	Oct. 31, 2011 Customer contracts, customer lists and distribution agreements Year	Oct. 31, 2010 Customer contracts, customer lists and distribution agreements	Oct. 31, 2011 Developed and core technology and patents Year	Oct. 31, 2010 Developed and core technology and patents	Oct. 31, 2011 Product trademarks	Oct. 31, 2010 Product trademarks	Oct. 31, 2011 Carrier relationships and trade name
Purchased intangible assets
Amortizable purchased intangible assets, gross	$ 13,908,000,000	$ 11,071,000,000							$ 6,346,000,000	$ 7,075,000,000	$ 7,226,000,000	$ 3,797,000,000	$ 336,000,000	$ 199,000,000
Amortizable purchased intangible assets, accumulated amortization	(4,441,000,000)	(4,946,000,000)							(2,376,000,000)	(3,436,000,000)	(1,944,000,000)	(1,418,000,000)	(121,000,000)	(92,000,000)
Amortizable purchased intangible assets, net	9,467,000,000	6,125,000,000							3,970,000,000	3,639,000,000	5,282,000,000	2,379,000,000	215,000,000	107,000,000
Indefinite-lived purchased intangible assets			9,000,000	301,000,000
Indefinite-lived purchased intangible assets, trade names					1,422,000,000			1,422,000,000
Purchased intangible assets, gross	15,339,000,000	12,794,000,000
Purchased intangible assets, net	10,898,000,000	7,848,000,000
Excess of fair value over carrying value for the indefinite-lived intangible assets under the sensitivity of the fair value calculation analysis							13,000,000
Excess of fair value over carrying value for the indefinite-lived intangible assets							144,000,000
Percentage of hypothetical decrease to the fair value of the intangible assets						10.00%
Weighted average useful live (in years)									8		7
Purchased intangibles assets and IPR&D related to acquisitions	4,700,000,000	2,700,000,000
Impairment loss															72,000,000
IPR&D reclassified to developed technology			290,000,000
Intangible assets that have reached end of amortization period	(4,700,000,000)	(2,500,000,000)
Goodwill and intangible assets recorded on balance sheet	$ 273,000,000