Income Taxes (Details) (USD $) In Millions	3 Months Ended	9 Months Ended
Jul. 31, 2011	Jul. 31, 2011
Income Taxes [Line Items]
Income Tax Expense (Benefit)	$ 1,476
Impact to additional paid-in capital for valuation allowance release	45	45
Likelihood of being realized upon settlement, percent		greater than 50%
Unrecognized Tax Benefits	113	113
Liability for unrecognized tax benefits	106	106
Significant Change in Unrecognized Tax Benefits is Reasonably Possible, Estimated Range of Change, Lower Bound	25	25
Significant Change in Unrecognized Tax Benefits is Reasonably Possible, Estimated Range of Change, Upper Bound	$ 100	$ 100

Adjustments to additional paid in capital release of valuation allowance

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Income Taxes [Line Items]

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Income Taxes Percent Likelihood Of Being Realized Upon Settlement

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The portion of the difference between total income tax expense or benefit as reported in the Income Statement and the expected income tax expense or benefit computed by applying the domestic federal statutory income tax rates to pretax income from continuing operations attributable to changes in the valuation allowance for deferred tax assets in the period.

+ References

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The estimated lower bound of the reasonably possible change in the total amount of the unrecognized tax benefit (that will significantly increase or decrease within twelve months of the balance sheet date) for a tax position taken.

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The estimated upper bound of the reasonably possible change in the total amount of the unrecognized tax benefit (that will significantly increase or decrease within twelve months of the balance sheet date) for a tax position taken.

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The gross amount of unrecognized tax benefits pertaining to uncertain tax positions taken in tax returns as of the balance sheet date.

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-Name FASB Interpretation (FIN)
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Reference 2: http://www.xbrl.org/2003/role/presentationRef
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The total amount of unrecognized tax benefits that, if recognized, would affect the effective tax rate.

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