Equity Method Investments (Details) - USD ($) $ in Millions	12 Months Ended
	Oct. 31, 2016	Oct. 31, 2015	Oct. 31, 2014	May 31, 2016
Schedule of Equity Method Investments [Line Items]
Investment in equity interests	$ 2,648	$ 0
Loss from equity interests	$ 76	$ 2	$ 0
H3C
Schedule of Equity Method Investments [Line Items]
Ownership	49.00%			49.00%
Investment in equity interests	$ 2,600			$ 2,739
Proportionate share of net assets of H3C				205
Basis difference				2,534
Equity method goodwill				1,674
Intangible assets				749
In-process research and development				188
Deferred tax liabilities				(152)
Other				$ 75
Loss from equity interests	$ 76
Weighted-average useful life	5 years
Amortization of difference in basis	$ 93
Elimination of intra-entity sales	15
Investment's earnings	$ 32
Unisplendour | H3C
Schedule of Equity Method Investments [Line Items]
Ownership				51.00%