Goodwill and Purchased Intangible Assets (Details 2) (USD $) In Millions, unless otherwise specified	6 Months Ended
	Apr. 30, 2012	Oct. 31, 2011
Purchased intangible assets
Amortizable purchased intangible assets, gross	$ 13,328	$ 13,908
Amortizable purchased intangible assets, accumulated amortization	(4,949)	(4,441)
Amortizable purchased intangible assets, net	8,379	9,467
Purchased intangible assets, gross	14,757	15,339
Purchased intangible assets, net	9,808	10,898
Amount of fully amortized intangible assets	428
Purchased intangible assets, purchase accounting adjustment	293
Purchased intangible assets, translation adjustments	(165)
In-process research and development ("IPR&D")
Purchased intangible assets
Indefinite-lived purchased intangible assets	7	9
Compaq trade name
Purchased intangible assets
Indefinite-lived purchased intangible assets, trade names	1,422	1,422
Customer contracts, customer lists and distribution agreements
Purchased intangible assets
Amortizable purchased intangible assets, gross	6,073	6,346
Amortizable purchased intangible assets, accumulated amortization	(2,503)	(2,376)
Amortizable purchased intangible assets, net	3,570	3,970
Developed and core technology and patents
Purchased intangible assets
Amortizable purchased intangible assets, gross	6,934	7,226
Amortizable purchased intangible assets, accumulated amortization	(2,319)	(1,944)
Amortizable purchased intangible assets, net	4,615	5,282
Product trademarks
Purchased intangible assets
Amortizable purchased intangible assets, gross	321	336
Amortizable purchased intangible assets, accumulated amortization	(127)	(121)
Amortizable purchased intangible assets, net	$ 194	$ 215