Supplementary Financial Information - Interest and Other, Net (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Jul. 31, 2018	Jul. 31, 2017	Jul. 31, 2018	Jul. 31, 2017
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Loss on extinguishment of debt	$ 0	$ 0	$ (126)	$ 0
Tax indemnifications	(3)	10	(676)	24
Interest expense on borrowings	(66)	(79)	(241)	(225)
Other, net	7	13	32	0
Interest and other, net	(62)	$ (56)	(1,011)	$ (201)
Adjustment to indemnification receivable	$ 676		$ 671