Supplementary Financial Information - Costs of Obtaining Contracts (Narrative) (Details) - USD ($) $ in Millions	12 Months Ended
	Oct. 31, 2025	Oct. 31, 2024	Oct. 31, 2023
Capitalized Contract Cost [Line Items]
Contract cost amortization	$ 68	$ 86
Contract liability	3,200	2,900	$ 2,700
Revenue recognized	1,500	1,400
Deferred contract fulfillment
Capitalized Contract Cost [Line Items]
Capitalized contract costs	33	36
Acquisition costs
Capitalized Contract Cost [Line Items]
Capitalized contract costs	$ 42	$ 50