Income Taxes (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
Jan. 31, 2012
Income Taxes [Line Items]
Income Taxes Percent Likelihood Of Being Realized Upon Settlement	50.00%
Liability for uncertain tax positions	$ 25
Unrecognized Tax Benefits that Would Impact Effective Tax Rate	29
Tax Adjustments, Settlements, and Unusual Provisions	12
Significant Change in Unrecognized Tax Benefits is Reasonably Possible, Estimated Range of Change, Lower Bound	0
Significant Change in Unrecognized Tax Benefits is Reasonably Possible, Estimated Range of Change, Upper Bound	$ 25

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Income Taxes Percent Likelihood Of Being Realized Upon Settlement

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- Definition

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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 740

-SubTopic 10

-Section 50

-Paragraph 15

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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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- Definition

Reflects the effects of adjustments of previously recorded tax expense, significant settlements of income tax disputes, and unusual tax positions or infrequent actions taken by the entity, including tax assessment reversal, IRS tax settlement and unusual repatriation of foreign earnings.

+ References

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-Name FASB Interpretation (FIN)

-Number 48

-Paragraph 10

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- Definition

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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-Publisher FASB

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-Glossary Unrecognized Tax Benefit

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The total amount of unrecognized tax benefits that, if recognized, would affect the effective tax rate.

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