Financial Instruments - Schedule of Pre-Tax Effect of Derivative Instruments in Cash Flow Hedging Relationships (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Jul. 31, 2018	Jul. 31, 2017	Jul. 31, 2018	Jul. 31, 2017
Pre-tax effect of derivative instruments in cash flow hedging relationships
Loss Recognized in Other Comprehensive Income (“OCI”) on Derivatives (Effective Portion)	$ 273	$ (519)	$ 19	$ (758)
Foreign currency contracts | Cash flow hedges
Pre-tax effect of derivative instruments in cash flow hedging relationships
Loss Recognized in Other Comprehensive Income (“OCI”) on Derivatives (Effective Portion)	273	(519)	19	(758)
(Loss) Gain Reclassified from Accumulated OCI Into Earnings (Effective Portion)	(17)	(38)	(363)	49
Foreign currency contracts | Cash flow hedges | Net revenue
Pre-tax effect of derivative instruments in cash flow hedging relationships
(Loss) Gain Reclassified from Accumulated OCI Into Earnings (Effective Portion)	(20)	(26)	(349)	89
Foreign currency contracts | Cash flow hedges | Cost of revenue
Pre-tax effect of derivative instruments in cash flow hedging relationships
(Loss) Gain Reclassified from Accumulated OCI Into Earnings (Effective Portion)	4	(13)	(14)	(32)
Foreign currency contracts | Cash flow hedges | Operating expenses
Pre-tax effect of derivative instruments in cash flow hedging relationships
(Loss) Gain Reclassified from Accumulated OCI Into Earnings (Effective Portion)	(1)	1	0	1
Foreign currency contracts | Cash flow hedges | Interest and other, net
Pre-tax effect of derivative instruments in cash flow hedging relationships
(Loss) Gain Reclassified from Accumulated OCI Into Earnings (Effective Portion)	$ 0	$ 0	$ 0	$ (9)