Supplementary Financial Information - Accounts Receivables, net (Details) - USD ($) $ in Millions	12 Months Ended
	Oct. 31, 2019	Oct. 31, 2018	Oct. 31, 2017	Oct. 31, 2019	Nov. 01, 2018	Oct. 31, 2018
Accounts Receivable, Net
Accounts receivable				$ 6,142		$ 5,242
Allowance for doubtful accounts	$ (111)	$ (101)	$ (107)	(111)		(129)
Accounts receivable, net				$ 6,031	$ 5,326	$ 5,113
Allowance for Doubtful Accounts Receivable
Balance at beginning of year	129	101	107
Provision for doubtful accounts	60	57	30
Deductions, net of recoveries	(78)	(29)	(36)
Balance at end of year	$ 111	$ 129	$ 101