Stockholders' Deficit - Schedule of Changes and reclassifications related to Other Comprehensive Income (Loss), net of taxes (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Jul. 31, 2019	Jul. 31, 2018	Jul. 31, 2019	Jul. 31, 2018
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Unrealized gains (losses) arising during the period			$ 228
Losses (gains) reclassified into earnings			(208)
Other comprehensive income (loss), net of taxes	$ 37	$ 275	(18)	$ 379
Change in unrealized gains (losses) on available-for-sale securities
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Unrealized gains (losses) arising during the period	0	2	0	(2)
Losses (gains) reclassified into earnings	0	0	3	(5)
Other comprehensive income (loss), net of taxes	0	2	3	(7)
Net unrealized gains (losses) on cash flow hedges
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Unrealized gains (losses) arising during the period	173	247	248	26
Losses (gains) reclassified into earnings	(72)	15	(225)	329
Other comprehensive income (loss), net of taxes	101	262	23	355
(Losses) gains arising during the period
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Unrealized gains (losses) arising during the period	(12)	1	(15)	1
Tax provision on amortization of actuarial loss and prior service benefit
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Losses (gains) reclassified into earnings	8	9	25	28
Curtailments, settlements and other
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Losses (gains) reclassified into earnings	(38)	1	(38)	2
Change in unrealized components of defined benefit plans
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Unrealized gains (losses) arising during the period			(15)
Losses (gains) reclassified into earnings			25
Other comprehensive income (loss), net of taxes	(42)	11	(28)	31
Change in cumulative translation adjustment
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Unrealized gains (losses) arising during the period			(5)
Losses (gains) reclassified into earnings			(11)
Change in cumulative translation adjustment	$ (22)	$ 0	$ (16)	$ 0

Amount after tax, before reclassification adjustments, of other comprehensive income (loss), attributable to parent.

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