Supplementary Financial Information - Schedule of Transferred Trade Receivables Not Collected from Third Parties (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Jul. 31, 2020	Jul. 31, 2019	Jul. 31, 2020	Jul. 31, 2019
Trade Receivables Sold and Cash Received [Roll Forward]
Balance at beginning of period	$ 124	$ 182	$ 235	$ 165
Trade receivables sold	2,231	2,311	7,411	7,836
Cash receipts	(2,254)	(2,330)	(7,544)	(7,838)
Foreign currency and other	8	(4)	7	(4)
Balance at end of period	$ 109	$ 159	$ 109	$ 159