Taxes on Earnings (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended		12 Months Ended
	Jul. 31, 2016	Jul. 31, 2015	Jul. 31, 2016	Jul. 31, 2015	Oct. 31, 2015
Major components of assets and liabilities included in distribution
Effective tax rate (percent)	22.00%	23.70%	21.70%	22.20%
U.S. federal statutory income tax rate (percent)			35.00%
Various tax expense (benefit) related to discrete items	$ 14	$ 28	$ (72)	$ 12
Tax benefits from restructuring charges	8	1	46	8
Tax benefit arising from the retroactive research and development credit			41	28
Tax expense from provision to return adjustments		7		36
Provision to return adjustments and other tax expense		$ 22		$ 12
Unrecognized tax benefits	9,600		9,600
Unrecognized tax benefits that would affect effective tax rate if realized	3,400		3,400
Increase in unrecognized tax benefits			385
Distribution of liabilities related solely to uncertain tax positions	732		732
Accrued income tax payable for interest and penalties	153		153
Reasonably possible reduction in existing unrecognized tax benefits within the next 12 months	5		5
Advance royalty proceeds received from multi-year intercompany licensing arrangements			1,100		$ 3,800
Royalty recognition term					5 years
Hewlett-Packard Enterprise
Major components of assets and liabilities included in distribution
Receivable for certain tax liabilities under the Tax Matters Agreement	$ 1,100		$ 1,100