Taxes - Additional Information (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended
Jan. 31, 2014
Taxes [Line Items]
Statutory federal income tax rate	35.00%
Gross unrecognized tax benefits	$ 115.0
Unrecognized tax benefits that would affect effective tax rate	115.0
Estimated potential decrease in underlying unrecognized tax benefits, minimum	0
Estimated potential decrease in underlying unrecognized tax benefits, maximum	36
Unrecognized tax benefits decrease resulting from settlement with IRS	$ 10

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Percentage of domestic federal statutory tax rate applicable to pretax income (loss).

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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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- Definition

Amount of unrecognized tax benefits pertaining to uncertain tax positions taken in tax returns.

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-Glossary Unrecognized Tax Benefit

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Amount of decrease in unrecognized tax benefits resulting from settlements with taxing authorities.

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

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