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, 2017	Jul. 31, 2016	Jul. 31, 2017	Jul. 31, 2016
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Other comprehensive income (loss), net of taxes	$ 184	$ (10)	$ 660	$ (162)
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			(12)
(Gains) losses reclassified into earnings			0
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			27
(Gains) losses reclassified into earnings			(196)
Change in unrealized components of defined benefit plans
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Other comprehensive (loss) income before reclassifications			662
(Gains) losses reclassified into earnings			169
Change in cumulative translation adjustment
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Other comprehensive (loss) income before reclassifications			10
(Gains) losses 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	6	7	(12)	10
(Gains) losses reclassified into earnings	0	(1)	0	1
Other comprehensive income (loss), net of taxes	6	6	(12)	11
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	(86)	149	27	116
(Gains) losses reclassified into earnings	5	(25)	(196)	(191)
Other comprehensive income (loss), net of taxes	(81)	124	(169)	(75)
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 (loss), net of taxes	214	50	831	152
Reclassifications of gains (losses) into earnings | Gains (losses) arising during the period
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
(Gains) losses reclassified into earnings	197	(11)	662	(12)
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) losses reclassified into earnings	52	67	215	199
Reclassifications of gains (losses) into earnings | Curtailments, settlements and other
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Other comprehensive income (loss), net of taxes	(35)	(6)	(46)	(35)
Reclassifications of gains (losses) into earnings | Change in cumulative translation adjustment
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Other comprehensive income (loss), net of taxes	$ 45	$ (190)	$ 10	$ (250)