Stockholders' Equity - Taxes Related to Other Comprehensive Income (Loss) (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Apr. 30, 2018	Apr. 30, 2017	Apr. 30, 2018	Apr. 30, 2017
Taxes on change in net unrealized losses on available-for-sale securities:
Tax provision on net unrealized (losses) gains arising during the period	$ 0	$ 0	$ 0	$ (1)
Taxes on change in net unrealized gains (losses) on available-for-sale securities	0	0	0	(1)
Taxes on change in net unrealized gains (losses) on cash flow hedges:
Tax (provision) benefit on net unrealized gains (losses) arising during the period	(11)	4	14	(27)
Tax (benefit) provision on net losses (gains) reclassified into earnings	(12)	13	(16)	45
Taxes on change in net unrealized (losses) gains on cash flow hedges	(23)	17	(2)	18
Taxes on change in unrealized components of defined benefit plans:
Tax provision on gains arising during the period	0	(1)	(1)	(25)
Tax benefit on amortization of actuarial loss and prior service benefit	(3)	(5)	(6)	(11)
Tax provision on curtailments, settlements and other	0	(7)	(7)	(14)
Taxes on change in unrealized components of defined benefit plans	(3)	(13)	(14)	(50)
Tax benefit on change in cumulative translation adjustment	4	0	1	1
Tax (provision) benefit on other comprehensive (loss) income	$ (22)	$ 4	$ (15)	$ (32)

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Amount of tax expense (benefit) for (increase) decrease in value of benefit obligation for change in actuarial assumptions and increase (decrease) in value of plan assets from experience different from that assumed of defined benefit plan, that has not been recognized in net periodic benefit (cost) credit.

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Amount of tax expense (benefit) for increase (decrease) to other comprehensive income from settlement and curtailment gain (loss) of defined benefit plan.

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Amount of tax expense (benefit), after reclassification adjustments of gain (loss) on foreign currency translation adjustments, foreign currency transactions designated and effective as economic hedges of a net investment in a foreign entity and intra-entity foreign currency transactions that are of a long-term-investment nature, attributable to parent entity.

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Amount of tax expense (benefit), after reclassification adjustments, of appreciation (loss) in value of unsold available-for-sale securities. Excludes amounts related to other than temporary impairment (OTTI) loss.

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Amount, after reclassification adjustment, of tax (expense) benefit for (increase) decrease in accumulated other comprehensive income of defined benefit plan.

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Amount of tax expense (benefit) of reclassification adjustment from accumulated other comprehensive income of accumulated gain (loss) realized from derivative instruments designated and qualifying as the effective portion of cash flow hedges and an entity's share of an equity investee's deferred hedging gain (loss).

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Amount of tax (expense) benefit for reclassification adjustment from accumulated other comprehensive (income) loss of defined benefit plan.

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Amount of tax expense (benefit) allocated to other comprehensive income (loss) attributable to parent entity.

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Amount of tax expense (benefit) before reclassification adjustments of unrealized holding gain (loss) on available-for-sale securities.

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