Stockholders' Equity - Changes and Reclassifications Related to Other Comprehensive Income (Loss), Net of Taxes (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Jul. 31, 2018	Jul. 31, 2017	Jul. 31, 2018	Jul. 31, 2017
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Other comprehensive income, net of taxes	$ 76	$ 184	$ 175	$ 660
Net unrealized gains (losses) on available-for-sale securities
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Other comprehensive (loss) income before reclassifications			(1)
Gains reclassified into earnings			(9)
Change in net unrealized (losses) gains on cash flow hedges
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Other comprehensive (loss) income before reclassifications			44
Gains reclassified into earnings			67
Change in unrealized components of defined benefit plans
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Other comprehensive (loss) income before reclassifications			(21)
Gains reclassified into earnings			132
Change in cumulative translation adjustment
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Other comprehensive (loss) income before reclassifications			(37)
Gains reclassified into earnings			0
Reclassifications of gains (losses) into earnings | Net unrealized gains (losses) on available-for-sale securities
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Other comprehensive (loss) income before reclassifications	(2)	6	(1)	(12)
Gains reclassified into earnings	0	0	(9)	0
Other comprehensive income, net of taxes	(2)	6	(10)	(12)
Reclassifications of gains (losses) into earnings | Change in net unrealized (losses) gains on cash flow hedges
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Other comprehensive (loss) income before reclassifications	129	(86)	44	27
Gains reclassified into earnings	(38)	5	67	(196)
Other comprehensive income, net of taxes	91	(81)	111	(169)
Reclassifications of gains (losses) into earnings | Change in unrealized components of defined benefit plans
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Other comprehensive income, net of taxes	25	214	111	831
Reclassifications of gains (losses) into earnings | (Losses) gains arising during the period
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Gains reclassified into earnings	(22)	197	(21)	662
Reclassifications of gains (losses) into earnings | Amortization of actuarial loss and prior service benefit
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Gains reclassified into earnings	43	52	133	215
Reclassifications of gains (losses) into earnings | Curtailments, settlements and other
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Other comprehensive income, net of taxes	4	(35)	(1)	(46)
Reclassifications of gains (losses) into earnings | Change in cumulative translation adjustment
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Other comprehensive income, net of taxes	$ (38)	$ 45	$ (37)	$ 10