Supplementary Financial Information - Schedule of Transferred Trade Receivables Not Collected from Third Parties (Details) - USD ($) $ in Millions	3 Months Ended
	Jan. 31, 2020	Jan. 31, 2019
Trade Receivables Sold and Cash Received Roll Forward
Balance at beginning of period	$ 235	$ 165
Trade receivables sold	2,857	3,036
Cash receipts	(3,004)	(3,010)
Foreign currency and other	0	3
Balance at end of period	$ 88	$ 194