Financial Instruments - Schedule of Pre-Tax Effect of Derivative Instruments in Cash Flow Hedging Relationships (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Apr. 30, 2019	Apr. 30, 2018	Apr. 30, 2019	Apr. 30, 2018
Pre-tax effect of derivative instruments in cash flow hedging relationships
Gain Recognized in Other Comprehensive Income (OCI) on Derivatives (Effective Portion)	$ 198	$ 297	$ 91	$ (254)
Foreign currency contracts | Cash flow hedges
Pre-tax effect of derivative instruments in cash flow hedging relationships
Gain Recognized in Other Comprehensive Income (OCI) on Derivatives (Effective Portion)	198	91	297	(254)
(Loss) Gain Reclassified from Accumulated OCI Into Earnings (Effective Portion)	(6)	173	(276)	(346)
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)	0	191	(277)	(329)
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)	(6)	(16)	0	(18)
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)	$ 0	$ (2)	$ 1	$ 1