Taxes on Earnings (Details) $ in Millions	3 Months Ended		9 Months Ended
	Jul. 31, 2020 USD ($) country	Jul. 31, 2019 USD ($)	Jul. 31, 2020 USD ($) country	Jul. 31, 2019 USD ($)
Income Tax Disclosure [Abstract]
Effective tax rate (percent)	2.20%	(375.40%)	11.40%	(36.10%)
Net tax benefit	$ 116	$ 1,100	$ 182	$ 1,100
Tax benefits related to audit settlements	102	1,000	143	1,000
Tax benefits related to restructuring charges	20		75
Tax benefits related to acquisition charges	4		20
Uncertain tax position charges	3		54
Tax benefits related to utilization of tax attributes		75		75
Tax benefits related to new guidance		57		78
Valuation allowance charges		98		98
Excess tax benefits				21
Unrecognized tax benefits	824		824
Unrecognized tax benefits that would affect effective tax rate if realized	680		680
Unrecognized tax benefits change			105
Accrued income tax payable for interest and penalties	37	$ 75	$ 37	$ 75
Likelihood of no resolution period			12 months
Reasonably possible decrease in existing unrecognized tax benefits within the next 12 months	$ 80		$ 80
Other countries with income tax jurisdiction | country	58		58