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Stockholders' Deficit - Schedule of Changes and Reclassifications Related to Other Comprehensive Income, Net of Taxes (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Jul. 31, 2020	Jul. 31, 2019	Jul. 31, 2020	Jul. 31, 2019
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Unrealized gains arising during the period			$ (238)
Gains reclassified into earnings			(145)
Other comprehensive (loss) income, net of taxes	$ (555)	$ 37	(380)	$ (18)
Change in unrealized gains (losses) on available-for-sale securities
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Unrealized gains arising during the period	2	0	1	0
Gains reclassified into earnings	0	0	0	3
Other comprehensive (loss) income, net of taxes	2	0	1	3
Net unrealized gains (losses) on cash flow hedges
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Unrealized gains arising during the period	(480)		(238)
Gains reclassified into earnings	(105)		(191)
Other comprehensive (loss) income, net of taxes	(585)		(429)
Net unrealized gains (losses) on cash flow hedges
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Unrealized gains arising during the period		173		248
Gains reclassified into earnings		(72)		(225)
Other comprehensive (loss) income, net of taxes		101		23
Tax benefit on losses arising during the period
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Unrealized gains arising during the period	(4)	(12)	(5)	(15)
Tax provision on amortization of actuarial loss and prior service benefit
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Gains reclassified into earnings	15	8	46	25
Curtailments, settlements and other
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Gains reclassified into earnings	2	(38)	3	(38)
Change in unrealized components of defined benefit plans
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Unrealized gains arising during the period			(5)
Gains reclassified into earnings			46
Other comprehensive (loss) income, net of taxes	13	(42)	44	(28)
Change in cumulative translation adjustment
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Unrealized gains arising during the period			4
Gains reclassified into earnings			0
Change in cumulative translation adjustment	$ 15	$ (22)	$ 4	$ (16)