Consolidated and Combined Statements of Comprehensive Income - USD ($) $ in Millions	12 Months Ended
	Oct. 31, 2017	Oct. 31, 2016	Oct. 31, 2015
Statement of Comprehensive Income [Abstract]
Net earnings	$ 344	$ 3,161	$ 2,461
Change in net unrealized losses on available-for-sale securities:
Net unrealized losses arising during the period	(8)	(4)	(10)
(Gains) losses reclassified into earnings	(4)	3	0
Change in unrealized (losses) gains on available-for-sale securities	(12)	(1)	(10)
Change in net unrealized (losses) gains on cash flow hedges:
Net unrealized gains arising during the period	46	226	481
Net gains reclassified into earnings	(145)	(270)	(480)
Change in unrealized gains (losses) on cash flow hedges	(99)	(44)	1
Change in unrealized components of defined benefit plans:
Gains (losses) arising during the period	944	(1,777)	(382)
Amortization of actuarial loss and prior service benefit	285	284	214
Curtailments, settlements and other	15	(18)	4
Plans transferred from former Parent during the period	0	0	(2,607)
Change in unrealized components of defined benefit plans	1,244	(1,511)	(2,771)
Cumulative translation adjustment arising during the period	(14)	(154)	(198)
Release of cumulative translation adjustment as a result of H3C and MphasiS divestitures	0	75	0
Change in foreign currency translation adjustment	(14)	(79)	(198)
Other comprehensive income (loss) before taxes	1,119	(1,635)	(2,978)
(Provision) benefit for taxes	(145)	51	211
Other comprehensive income (loss), net of taxes	974	(1,584)	(2,767)
Comprehensive income (loss)	$ 1,318	$ 1,577	$ (306)